Process for producing polycarbonates and a coordination complex used therefor

ABSTRACT

The complex of the present invention containing an onium salt and a central Lewis acidic metal has a high catalytic activity at a high temperature for the copolymerization of an epoxide and carbon dioxide to produce a high molecular weight poly-carbonate.

FIELD OF THE INVENTION

The present invention relates to a process for producing a polycarbonateusing an epoxide and carbon dioxide and a novel coordination complexwhich is useful as a catalyst therefor.

BACKGROUND OF THE INVENTION

Aliphatic polycarbonates are known to be biodegradable and widely usedfor packages, coatings and others. An aliphatic polycarbonate can beprepared by copolymerizing an epoxide with carbon dioxide, which isenvironment-friendly since a toxic compound such as phosgene is notused. For such a process, there have been developed various types ofcatalysts, e.g., metallic zinc compounds.

There have recently been reported highly active binary catalyst systemscomprising (Salen)Co or (Salen)Cr derivatives (wherein H₂Salen isN,N′-bis(3,5-dialkylsalicylidene)-1,2-cyclohexanediamine) combined withan onium salt such as [R₄N]Cl and PPNCl (bis(triphenylphosphine)iminiumchloride) or a base such as an amine and phosphine. [(Salen)Co system:(a) Lu, X.-B.; Shi, L.; Wang, Y.-M.; Zhang, R.; Zhang, Y.-J.; Peng,X.-J.; Zhang, Z.-C.; Li, B. J. Am. Chem. Soc. 2006, 128, 1664; (b)Cohen, C. T. Thomas, C. M. Peretti, K. L. Lobkovsky, E. B. Coates, G. W.Dalton Trans. 2006, 23.; (c) Paddock, R. L. Nguyen, S. T. Macromolecules2005, 38, 6251; (Salen)Cr system: (a) Darensbourg, D. J.; Phelps, A. L.;Gall, N. L.; Jia, L. Acc. Chem. Res. 2004, 37, 836; (b) Darensbourg, D.J.; Mackiewicz, R. M. J. Am. Chem. Soc. 2005, 127, 14026]

In case of using a binary catalyst system comprising a (Salen)Cocompound, the oxygen atom of an epoxide coordinates to the central Coatom having Lewis acid character and carbonate anion generated by theaction of an onium salt or bulky amine base reacts with the activatedepoxide through nucleophilic attack as shown below. With this system,the polymerization was conducted typically under the conditions that[epoxide]/[catalyst] is 2,000 and temperature is below 45° C., with themaximum turnover number (TON) of 980 and the turnover frequency (TOF) of1400 h⁻¹.

Coates, G. W. et al. have also developed a highly active catalystcomposed of a zinc complex having a β-diketiminate ligand, which shows ahigh turnover rate of 1,116 turnover/hr [Coates, G. W. Moore, D. R.Angew. Chem., Int. Ed. 2004, 6618; U.S. Pat. No. 6,133,402]. Coates etal. achieved a still higher turnover rate of 2,300 turnover/hr when azinc catalyst having a similar structure is used [J. Am. Chem. Soc. 125,11911-11924 (2003)]. The catalytic action of the zinc complex comprisingβ-diketiminate ligand has been proposed to occur as shown below [Moore,D. R.; Cheng, M.; Lobkovsky, E. B.; Coates, G. W. J. Am. Chem. Soc.2003, 125, 11911].

Under above-mentioned mechanisms, the catalystic systems have somedrawbacks that will prevent them from being commercially available. Itis conceptually difficult to achieve a high turnover number (TON) underthese mechanisms. In order to achieve a high TON, the catalyst shouldtherefore be active even at a high [monomer]/[catalyst] ratio condition.However, at this condition, the chance for the chain-growing carbonateunit to meet the coordinated epoxide is diminished, consequentlyresulting in a low activity. Because all the addition polymerizationreaction is exothermic, heat removal during polymerization is a keyissue in designing the process. If the catalyst works at a reasonablyhigh temperature, we can remove the heat by using ambient water or air,but if the catalyst works only at a low temperature, for instance, roomtemperature, we have to use some cryogen, which makes the processexpensive. In a solution or bulk polymerization, the attainableconversion of monomer to the polymer is limited by the viscosity causedby formation of polymer. If we can run the polymerization at a highertemperature, we can convert more monomers to polymers because theviscosity is reduced as the temperature is increased. For thepropagation mechanism shown above, the ΔS^(‡) is negative and theactivation energy (ΔG^(‡)) for the step increases as the temperatureincreases, leading to a lower activity at a higher temperature.

The TON and TOF values achieved by a binary catalyst system comprising a(Salen)Co compound or a zinc complex having a β-diketiminate ligand arestill low enough to warrant to further improvement, because low activitymeans higher catalyst cost and higher levels of catalyst-derived metalresidue in the resin. This metal residue either colours the resin orcauses toxicity. While TON of 980 attained with a binary catalyst systemcomprising a (Salen)Co compound for CO₂/(propylene oxide)copolymerization, the residual cobalt level in the resin reached 600 ppmunless it was removed.

Therefore, there has been a need to develop a catalyst which is capableof polymerizing an acyclic epoxide or a cyclic epoxide at a high rateunder a high-temperature industrial condition or at a highly dilutedcondition, to produce a polymer having a high molecular weight.

Further, there have been made many unsuccessful attempts to recovercatalysts from polymer products after polymerization, and, therefore, itis another object of the present invention to provide an effective wayto recover active catalysts after use.

SUMMARY OF THE INVENTION

In accordance with one aspect of the present invention, there isprovided a process for producing a polycarbonate comprising subjectingan epoxide and carbon dioxide to a copolymerization reaction in thepresence of a complex, wherein the complex comprises one central metalatom which serves as a Lewis acid site and at least one functionalmoiety selected from the group consisting of those represented byformula (1), formula (2) and formula (3):

wherein

Z is nitrogen or phosphorus;

X is halogen; C₆-C₂₀ aryloxy; C₆-C₂₀ aryloxy having one or morefunctional moieties selected from the group consisting of halogen,nitrogen, oxygen, silicon, sulfur and phosphorus; C₁-C₂₀ carboxy; C₁-C₂₀carboxy having one or more functional moieties selected from the groupconsisting of halogen, nitrogen, oxygen, silicon, sulfur and phosphorus;C₁-C₂₀ alkoxy; C₁-C₂₀ alkoxy having one or more functional moietiesselected from the group consisting of halogen, nitrogen, oxygen,silicon, sulfur and phosphorus; C₁-C₂₀ alkylsulfonato; C₁-C₂₀alkylsulfonato having one or more functional moieties selected from thegroup consisting of halogen, nitrogen, oxygen, silicon, sulfur andphosphorus; C₁-C₂₀ amido; or C₁-C₂₀ amido having one or more functionalmoieties selected from the group consisting of halogen, nitrogen,oxygen, silicon, sulfur and phosphorus;

R¹¹, R¹², R¹³, R²¹, R²², R²³, R²⁴ and R²⁵ are each independentlyhydrogen; C₁-C₂₀ alkyl; C₁-C₂₀ alkyl having one or more functionalmoieties selected from the group consisting of halogen, nitrogen,oxygen, silicon, sulfur and phosphorus; C₂-C₂₀ alkenyl; C₂-C₂₀ alkenylhaving one or more functional moieties selected from the groupconsisting of halogen, nitrogen, oxygen, silicon, sulfur and phosphorus;C₇-C₂₀ alkylaryl; C₇-C₂₀ alkylaryl having one or more functionalmoieties selected from the group consisting of halogen, nitrogen,oxygen, silicon, sulfur and phosphorus; C₇-C₂₀ arylalkyl; C₇-C₂₀arylalkyl having one or more functional moieties selected from the groupconsisting of halogen, nitrogen, oxygen, silicon, sulfur and phosphorus;or a metalloid radical of group XIV metal substituted by hydrocarbyl,two of R¹¹, R¹² and R¹³, or two of R²¹, R²², R²³, R²⁴ and R²⁵ beingoptionally fused together to form a bridged structure;

R³¹, R³² and R³³ are each independently hydrogen; C₁-C₂₀ alkyl; C₁-C₂₀alkyl having one or more functional moieties selected from the groupconsisting of halogen, nitrogen, oxygen, silicon, sulfur and phosphorus;C₂-C₂₀ alkenyl; C₂-C₂₀ alkenyl having one or more functional moietiesselected from the group consisting of halogen, nitrogen, oxygen,silicon, sulfur and phosphorus; C₇-C₂₀ alkylaryl; C₇-C₂₀ alkylarylhaving one or more functional moieties selected from the groupconsisting of halogen, nitrogen, oxygen, silicon, sulfur and phosphorus;C₇-C₂₀ arylalkyl; C₇-C₂₀ arylalkyl having one or more functionalmoieties selected from the group consisting of halogen, nitrogen,oxygen, silicon, sulfur and phosphorus; or a metalloid radical of groupXIV metal substituted by hydrocarbyl, two of R³¹, R³² and R³³ beingoptionally fused together to form a bridged structure;

X′ is oxygen, sulfur or N—R;

R is hydrogen; C₁-C₂₀ alkyl; C₁-C₂₀ alkyl having one or more functionalmoieties selected from the group consisting of halogen, nitrogen,oxygen, silicon, sulfur and phosphorus; C₂-C₂₀ alkenyl; C₂-C₂₀ alkenylhaving one or more functional moieties selected from the groupconsisting of halogen, nitrogen, oxygen, silicon, sulfur and phosphorus;C₇-C₂₀ alkylaryl; C₇-C₂₀ alkylaryl having one or more functionalmoieties selected from the group consisting of halogen, nitrogen,oxygen, silicon, sulfur and phosphorus; C₇-C₂₀ arylalkyl; C₇-C₂₀arylalkyl having one or more functional moieties selected from the groupconsisting of halogen, nitrogen, oxygen, silicon, sulfur and phosphorus.

In accordance with another aspect of the present invention, thecatalytic complex may be recovered by a process comprising the steps oftreating the reaction mixture containing the polycarbonate and thecomplex with a composite-forming material to form a composite of thecomplex and the composite-forming material; removing the composite fromthe reaction mixture; and recovering the complex from the composite bytreating the composite in a medium which does not dissolve thecomposite-forming material with an acid and/or a non-reactive metalsalt, and isolating the complex released into the medium.

In accordance with further another aspect of the present invention,there is provided a polycarbonate produced by the above process, whereinthe metal content of the polycarbonate is below 15 ppm.

In accordance with further another aspect of the present invention,there is provided a complex of formula (4a):

wherein

M is Co or Cr;

X′ is each independently halogen; C₆-C₂₀ aryloxy unsubstituted orsubstituted by nitro; or C₁-C₂₀ carboxy unsubstituted or substituted byhalogen;

A is oxygen;

Q is trans-1,2-cyclohexylene, ethylene or substituted ethylene;

R¹, R², R⁴, R⁶, R⁷ and R⁹ are hydrogen;

R⁵ and R¹⁰ are each independently hydrogen, tert-butyl, methyl orisopropyl;

one or both of R³ and R⁸ are —[YR⁴¹_(3-m){(CR⁴²R⁴³)_(n)NR⁴⁴R⁴⁵R⁴⁶}_(m)]X′_(m) or —[PR⁵¹R⁵²═N═PR⁵³R⁵⁴R⁵⁵]X′,the other being hydrogen, methyl, isopropyl or tert-butyl;

Y is C or Si;

R⁴¹, R⁴², R⁴³, R⁴⁴, R⁴⁵, R⁴⁶, R⁵¹, R⁵², R⁵³, R⁵⁴ and R⁵⁵ are eachindependently hydrogen; C₁-C₂₀ alkyl; C₁-C₂₀ alkyl having one or morefunctional moieties selected from the group consisting of halogen,nitrogen, oxygen, silicon, sulfur and phosphorous; C₂-C₂₀ alkenyl;C₂-C₂₀ alkenyl having one or more functional moieties selected from thegroup consisting of halogen, nitrogen, oxygen, silicon, sulfur andphosphorous; C₇-C₂₀ alkylaryl; C₇-C₂₀ alkylaryl having one or morefunctional moieties selected from the group consisting of halogen,nitrogen, oxygen, silicon, sulfur and phosphorous; C₇-C₂₀ arylalkyl;C₇-C₂₀ arylalkyl having one or more functional moieties selected fromthe group consisting of halogen, nitrogen, oxygen, silicon, sulfur andphosphorous; or a metalloid radical of group XIV metal substituted byhydrocarbyl, two of R⁴⁴, R⁴⁵ and R⁴⁶, or two of R⁵¹, R⁵², R⁵³, R⁵⁴ andR⁵⁵ being optionally fused together to form a bridged structure;

m is an integer in the range of 1 to 3; and

n is an integer in the range of 1 to 20.

In accordance with further another aspect of the present invention,there is provided a compound of formula (7a) which may be used forproducing a complex of formula (4a):

wherein

A is oxygen;

Q is trans-1,2-cyclohexylene, ethylene or substituted ethylene;

R¹, R², R⁴, R⁶, R⁷ and R⁹ are hydrogen;

R⁵ and R¹⁰ are each independently hydrogen, tent-butyl, methyl orisopropyl;

one or both of R³ and R⁸ are —[YR⁴¹_(3-m){(CR⁴²R⁴³)_(n)NR⁴⁴R⁴⁵R⁴⁶}_(m)]X′_(m) or —[PR⁵¹R⁵²═N═PR⁵³R⁵⁴R⁵⁵]X′,and the other is hydrogen, methyl, isopropyl or tert-butyl;

X′ is as defined for formula (4a);

Y is C or Si;

R⁴¹, R⁴², R⁴³, R⁴⁴, R⁴⁵, R⁴⁶, R⁵¹, R⁵², R⁵³, R⁵⁴and R⁵⁵ are eachindependently hydrogen; C₁-C₂₀ alkyl; C₁-C₂₀ alkyl having one or morefunctional moieties selected from the group consisting of halogen,nitrogen, oxygen, silicon, sulfur and phosphorous; C₂-C₂₀ alkenyl;C₂-C₂₀ alkenyl having one or more functional moieties selected from thegroup consisting of halogen, nitrogen, oxygen, silicon, sulfur andphosphorous; C₇-C₂₀ alkylaryl; C₇-C₂₀ alkylaryl having one or morefunctional moieties selected from the group consisting of halogen,nitrogen, oxygen, silicon, sulfur and phosphorous; C₇-C₂₀ arylalkyl;C₇-C₂₀ arylalkyl having one or more functional moieties selected fromthe group consisting of halogen, nitrogen, oxygen, silicon, sulfur andphosphorous; or a metalloid radical of group XIV metal substituted byhydrocarbyl, two of R⁴⁴, R⁴⁵ and R⁴⁶, or two of R⁵¹, R⁵², R⁵³, R⁵⁴ andR⁵⁵ being optionally fused together to form a bridged structure;

m is an integer in the range of 1 to 3; and

n is an integer in the range of 1 to 20.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects and features of the present invention willbecome apparent from the following description of the invention, whentaken in conjunction with the accompanying drawings, which respectivelyshow:

FIG. 1: a schematic diagram of the step of treating the reaction mixturecontaining the polycarbonate and the complex with a composite-formingmaterial to form a composite of the complex and the composite-formingmaterial;

FIGS. 2 and 3: schematic diagrams illustrating mechanisms for recoveringcatalytic complexes; and

FIG. 4: optical densities of the copolymers obtained in Examples 23 to26 and Comparative Example 6.

DETAILED DESCRIPTION OF THE INVENTION

According to an embodiment of the present invention, a polycarbonate maybe produced by copolymerizing an epoxide and carbon dioxide in thepresence of a catalytic complex having at least one functional groupselected from the group consisting of those represented by (1), formula(2) and formula (3), and a central metal which is a Lewis acid site.

Examples of the epoxide compound which may be used in thecopolymerization are selected from the group consisting of C₂-C₂₀alkylene oxide unsubstituted or substituted by halogen or alkoxy, C₄-C₂₀cycloalkene oxide unsubstituted or substituted by halogen or alkoxy, andC₈-C₂₀ styrene oxide unsubstituted or substituted by halogen, alkoxy oralkyl.

Particular examples of the epoxide compound may include ethylene oxide,propylene oxide, butene oxide, pentene oxide, hexene oxide, octeneoxide, decene oxide, dodecene oxide, tetradecene oxide, hexadeceneoxide, octadecene oxide, butadiene monoxide, 1,2-epoxy-7-octene,epifluorohydrin, epichlorohydrin, epibromohydrin, isopropyl glycidylether, butyl glycidyl ether, tert-butyl glycidyl ether, 2-ethylhexylglycidyl ether, allyl glycidyl ether, cyclopentene oxide, cyclohexeneoxide, cyclooctene oxide, cyclododecene oxide, α-pinene oxide,2,3-epoxynorbornene, limonene oxide, dieldrine, 2,3-epoxypropylbenzene,styrene oxide, phenylpropylene oxide, stilbene oxide, chlorostilbeneoxide, dichlorostilbene oxide, 1,2-epoxy-3-phenoxypropane,benzyloxymethyl oxirane, glycidyl-methylphenyl ether,chlorophenyl-2,3-epoxypropyl ether, epoxypropyl methoxyphenyl ether,biphenyl glycidyl ether, glycidyl naphthyl ether, etc.

According to another embodiment of the present invention, thepolymerization reaction may be conducted in a solvent to obtain asolution of the polycarbonate and the complex.

The organic solvent may include aliphatic hydrocarbon, such as pentane,octane, decane and cyclohexane; aromatic hydrocarbon, such as benzene,toluene and xylene; halogenated hydrocarbon, such as chloromethane,methylene chloride, chloroform, carbon tetrachloride,1,1-dichloroethane, 1,2-dichloroethane, ethyl chloride, trichloroethane,1-chloropropane, 2-chloropropane, 1-chlorobutane, 2-chlorobutane,1-chloro-2-methylpropane, chlorobenzene and bromobenzene, and thecombination thereof. Preferably, bulk polymerization is performed, inwhich the epoxide compound serves as a solvent.

The volume ratio of the solvent to the epoxide compound may be from0:100 to 99:1, preferably from 0:100 to 90:1.

The molar ratio of the epoxide to the catalyst may be from 1,000:1 to500,000:1, preferably from 10,000:1 to 100,000:1. At this time, theturnover rate of the catalyst is 500 turnover/hr or more.

The pressure of carbon dioxide may be in the range of from 1 to 100 atm,preferably 2-50 atm. The polymerization temperature may be in the rangeof from 20 to 120° C., preferably from 50 to 100° C.

The polycarbonate may be produced using a polymerization method, such asbatch, semi-batch, or continuous process. In the batch or semi-batchprocess, the reaction time may be from 1 to 24 hours, preferably from1.5 to 6 hours. Further, in the continuous process, the mean residencetime of the catalyst is preferably from 1 to 24 hours.

According to the method of the present invention, a polycarbonate havinga number average molecular weight (Mn) of 5,000 to 1,000,000 and amolecular weight distribution index (Mw/Mn) of 1.05 to 4.0 may beproduced. The number average molecular weight (Mn) and the weightaverage molecular weight (Mw) are measured by gel permeationchromatography (GPC).

The polycarbonate thus produced composed of at least 90% carbonate bond,often at least 99% carbonate bond, and it is easily biodegradable anduseful for packaging and coating.

The polymerizing process of the present invention employs a complexcontaining at least one functional group selected from the groupconsisting of those represented by (1), formula (2) and formula (3), anda central Lewis acidic metal.

A preferable embodiment of “complexes including a functional groupselected from the group consisting of those represented formula (1),formula (2) and formula (3), and a central Lewis acidic metal isrepresented by formula (4):

wherein

M is a metal;

X′ is a neutral or a monovalent anion ligand;

A is oxygen or sulfur;

Q is C₁-C₂₀ alkylene; C₁-C₂₀ alkylene having one or more functionalmoieties selected from the group consisting of halogen, nitrogen,oxygen, silicon, sulfur and phosphorous; C₃-C₂₀ cycloalkyl diradical;C₃-C₂₀ cycloalkyl diradical having one or more functional moietiesselected from the group consisting of halogen, nitrogen, oxygen,silicon, sulfur and phosphorous; C₆-C₃₀ aryl diradical; C₆-C₃₀ aryldiradical having one or more functional moieties selected from the groupconsisting of halogen, nitrogen, oxygen, silicon, sulfur andphosphorous; C₁-C₂₀ dioxy radical; or C₁-C₂₀ dioxy radical having one ormore functional moieties selected from the group consisting of halogen,nitrogen, oxygen, silicon, sulfur and phosphorous;

R¹ to R¹⁰ are each independently hydrogen; C₁-C₂₀ alkyl; C₁-C₂₀ alkylhaving one or more functional moieties selected from the groupconsisting of halogen, nitrogen, oxygen, silicon, sulfur andphosphorous; C₂-C₂₀ alkenyl; C₂-C₂₀ alkenyl having one or morefunctional moieties selected from the group consisting of halogen,nitrogen, oxygen, silicon, sulfur and phosphorous; C₇-C₂₀ alkylaryl;C₇-C₂₀ alkylaryl having one or more functional moieties selected fromthe group consisting of halogen, nitrogen, oxygen, silicon, sulfur andphosphorous; C₇-C₂₀ arylalkyl; C₇-C₂₀ arylalkyl having one or morefunctional moieties selected from the group consisting of halogen,nitrogen, oxygen, silicon, sulfur and phosphorous; or a metalloidradical of group XIV metal substituted by hydrocarbyl, two of R¹ to R¹⁰being optionally fused together to form a bridged structure; and atleast one of R¹ to R¹⁰ is a functional group selected from the groupconsisting of those represented by formula (1), formula (2) and formula(3).

Although a compound having the functional moiety of formula (1) has beenknown, e.g., J. Chem. Soc., Dlaton Trans., 2001, 991; Tetrahedron Lett.2003, 44, 6813; Journal of Catalysis 2004, 221, 234, the use of thecompound as a catalyst for polymerization of an epoxide and carbondioxide has not been suggested.

The more preferred embodiment of the complex according to presentinvention may be represented by formula (4a)

wherein

M is Co or Cr;

X′ is each independently halogen; C₆-C₂₀ aryloxy unsubstituted orsubstituted by nitro; or C₁-C₂₀ carboxy unsubstituted or substituted byhalogen;

A is oxygen;

Q is trans-1,2-cyclohexylene, ethylene or substituted ethylene;

R¹, R², R⁴, R⁶, R⁷ and R⁹ are hydrogen;

R⁵ and R¹⁰ are each independently hydrogen, tert-butyl, methyl orisopropyl;

one or both of R³ and R⁸ are —[YR⁴¹_(3-m){(CR⁴²R⁴³)_(n)NR⁴⁴R⁴⁵R⁴⁶}_(m)]X′_(m) or —[PR⁵¹R⁵²═N═PR⁵³R⁵⁴R⁵⁵]X′,the other being hydrogen, methyl, isopropyl or tert-butyl;

Y is C or Si;

R⁴¹, R⁴², R⁴³, R⁴⁴, R⁴⁵, R⁴⁶, R⁵¹, R⁵², R⁵³, R⁵⁴ and R⁵⁵ are eachindependently hydrogen; C₁-C₂₀ alkyl; C₁-C₂₀ alkyl having one or morefunctional moieties selected from the group consisting of halogen,nitrogen, oxygen, silicon, sulfur and phosphorous; C₂-C₂₀ alkenyl;C₂-C₂₀ alkenyl having one or more functional moieties selected from thegroup consisting of halogen, nitrogen, oxygen, silicon, sulfur andphosphorous; C₇-C₂₀ alkylaryl; C₇-C₂₀ alkylaryl having one or morefunctional moieties selected from the group consisting of halogen,nitrogen, oxygen, silicon, sulfur and phosphorous; C₇-C₂₀ arylalkyl;C₇-C₂₀ arylalkyl having one or more functional moieties selected fromthe group consisting of halogen, nitrogen, oxygen, silicon, sulfur andphosphorous; or a metalloid radical of group XIV metal substituted byhydrocarbyl, two of R⁴⁴, R⁴⁵ and R⁴⁶, or two of R⁵¹, R⁵², R⁵³, R⁵⁴ andR⁵⁵ being optionally fused together to form a bridged structure;

m is an integer in the range of 1 to 3; and

n is an integer in the range of 1 to 20.

More specific examples of the complexes according to present inventionare represented by formula (5a) to formula (5e):

wherein

M is Co or Cr;

R⁶¹, R⁶² and R⁶³ are each independently hydrogen, methyl, isopropyl ortent-butyl;

X is halogen; C₆-C₂₀ aryloxy; C₆-C₂₀ aryloxy having one or morefunctional moieties selected from the group consisting of halogen,nitrogen, oxygen, silicon, sulfur and phosphorous; C₁-C₂₀ carboxy;C₁-C₂₀ carboxy having one or more functional moieties selected from thegroup consisting of halogen, nitrogen, oxygen, silicon, sulfur andphosphorous; C₁-C₂₀ alkoxy; C₁-C₂₀ alkoxy having one or more functionalmoieties selected from the group consisting of halogen, nitrogen,oxygen, silicon, sulfur and phosphorous; C₁-C₂₀ alkylsulfonato; C₁-C₂₀alkylsulfonato having one or more functional moieties selected from thegroup consisting of halogen, nitrogen, oxygen, silicon, sulfur andphosphorous; C₁-C₂₀ amido; or C₁-C₂₀ amido having one or more functionalmoieties selected from the group consisting of halogen, nitrogen,oxygen, silicon, sulfur and phosphorous; and

n is an integer in the range of 1 to 20.

Still more specific examples of the complexes according to presentinvention are represented by formula (6a) to formula (60:

wherein X is 2,4-dinitrophenoxy;

wherein X is 2,4-dinitrophenoxy;

wherein X is Cl;

wherein X is 2,4-dinitrophenoxy, and R is methyl, isopropyl ortert-butyl;

wherein X is 2,4-dinitrophenoxy, and R is methyl, isopropyl ortert-butyl;

wherein X is Cl.

The complexes of formula (4) can be synthesized from the compound offormula (7) using a method similar to those known in the art, e.g.,Hobday, M. D.; Smith, T. D.; Coord. Chem. Rev. vol. 9, 1972-1973, 311;Cohen, C. T.; Thomas, C. M.; Peretti, K. L.; Lobkovsky, E. B.; Coates,G. W.; Dalton Trans. 2006, 237.

wherein

A is oxygen or sulfur;

Q is C₁-C₂₀ alkylene; C₁-C₂₀ alkylene having one or more functionalmoieties selected from the group consisting of halogen, nitrogen,oxygen, silicon, sulfur and phosphorous; C₃-C₂₀ cycloalkyl diradical;C₃-C₂₀ cycloalkyl diradical having one or more functional moietiesselected from the group consisting of halogen, nitrogen, oxygen,silicon, sulfur and phosphorous; C₆-C₃₀ aryl diradical; C₆-C₃₀ aryldiradical having one or more functional moieties selected from the groupconsisting of halogen, nitrogen, oxygen, silicon, sulfur andphosphorous; C₁-C₂₀ dioxy radical; or C₁-C₂₀ dioxy radical having one ormore functional moieties selected from the group consisting of halogen,nitrogen, oxygen, silicon, sulfur and phosphorous;

R¹ to R¹⁰ are each independently hydrogen; C₁-C₂₀ alkyl; C₁-C₂₀ alkylhaving one or more functional moieties selected from the groupconsisting of halogen, nitrogen, oxygen, silicon, sulfur andphosphorous; C₂-C₂₀ alkenyl; C₂-C₂₀ alkenyl having one or morefunctional moieties selected from the group consisting of halogen,nitrogen, oxygen, silicon, sulfur and phosphorous; C₇-C₂₀ alkylaryl;C₇-C₂₀ alkylaryl having one or more functional moieties selected fromthe group consisting of halogen, nitrogen, oxygen, silicon, sulfur andphosphorous; C₇-C₂₀ arylalkyl; C₇-C₂₀ arylalkyl having one or morefunctional moieties selected from the group consisting of halogen,nitrogen, oxygen, silicon, sulfur and phosphorous; or a metalloidradical of group XIV metal substituted by hydrocarbyl, two of R¹ to R¹⁰being optionally fused together to form a bridged structure; and

at least one of R¹ to R¹⁰ is a functional group selected from the groupconsisting of those represented by formula (1), formula (2) and formula(3).

In case X in the function group of formula (1) or formula (2) interruptsthe introduction of a metal, X may be replaced by BF₄ anion which isless reactive, and, after the introduction of the metal into thecompound, BF₄ anion may be replaced by X.

Similarly, the complexes of formula (4a) can be synthesized from thecompound of formula (7a):

wherein

A is oxygen;

Q is trans-1,2-cyclohexylene, ethylene or substituted ethylene;

R¹, R², R⁴, R⁶, R⁷ and R⁹ are hydrogen;

R⁵ and R¹⁰ are each independently hydrogen, tert-butyl, methyl orisopropyl;

one or both of R³ and R⁸ are —[YR⁴¹_(3-m){(CR⁴²R⁴³)_(n)NR⁴⁴R⁴⁵R⁴⁶}_(m)]X′_(m) or —[PR⁵¹R⁵²═N═PR⁵³R⁵⁴R⁵⁵]X′,and the other is hydrogen, methyl, isopropyl or tert-butyl;

X′ is as defined for formula (4a);

Y is C or Si;

R⁴¹, R⁴², R⁴³, R⁴⁴, R⁴⁵, R⁴⁶, R⁵¹, R⁵², R⁵³, R⁵⁴ and R⁵⁵ are eachindependently hydrogen; C₁-C₂₀ alkyl; C₁-C₂₀ alkyl having one or morefunctional moieties selected from the group consisting of halogen,nitrogen, oxygen, silicon, sulfur and phosphorous; C₂-C₂₀ alkenyl;C₂-C₂₀ alkenyl having one or more functional moieties selected from thegroup consisting of halogen, nitrogen, oxygen, silicon, sulfur andphosphorous; C₇-C₂₀ alkylaryl; C₇-C₂₀ alkylaryl having one or morefunctional moieties selected from the group consisting of halogen,nitrogen, oxygen, silicon, sulfur and phosphorous; C₇-C₂₀ arylalkyl;C₇-C₂₀ arylalkyl having one or more functional moieties selected fromthe group consisting of halogen, nitrogen, oxygen, silicon, sulfur andphosphorous; or a metalloid radical of group XIV metal substituted byhydrocarbyl, two of R⁴⁴, R⁴⁵ and R⁴⁶, or two of R⁵¹, R⁵², R⁵³, R⁵⁴ andR⁵⁵ being optionally fused together to form a bridged structure;

m is an integer in the range of 1 to 3; and

n is an integer in the range of 1 to 20.

Particular examples of the compound of formula (7a) are the compounds offormula (8a) to formula (8e):

wherein

R⁶¹, R⁶² and R⁶³ are each independently hydrogen, methyl, isopropyl ortert-butyl;

X is halogen; BF₄; C₆-C₂₀ aryloxy; C₆-C₂₀ aryloxy having one or morefunctional moieties selected from the group consisting of halogen,nitrogen, oxygen, silicon, sulfur and phosphorous; C₁-C₂₀ carboxy;C₁-C₂₀ carboxy having one or more functional moieties selected from thegroup consisting of halogen, nitrogen, oxygen, silicon, sulfur andphosphorous; C₁-C₂₀ alkoxy; C₁-C₂₀ alkoxy having one or more functionalmoieties selected from the group consisting of halogen, nitrogen,oxygen, silicon, sulfur and phosphorous; C₁-C₂₀ alkylsulfonato; C₁-C₂₀alkylsulfonato having one or more functional moieties selected from thegroup consisting of halogen, nitrogen, oxygen, silicon, sulfur andphosphorous; C₁-C₂₀ amido; or C₁-C₂₀ amido having one or more functionalmoieties selected from the group consisting of halogen, nitrogen,oxygen, silicon, sulfur and phosphorous; and

n is an integer in the range of 1 to 20.

More particular examples of the compound of formula (7) are thecompounds of formula (9a) to formula (9f):

wherein X is halogen, BF₄ or 2,4-dinitrophenoxy;

wherein X is halogen, BF₄ or 2,4-dinitrophenoxy;

wherein X is halogen, BF₄ or 2,4-dinitrophenoxy;

wherein X is halogen, BF₄ or 2,4-dinitrophenoxy, and R is methyl,isopropyl or tert-butyl;

wherein X is halogen, BF₄ or 2,4-dinitrophenoxy, and R is methyl,isopropyl or tert-butyl.

wherein X is Cl.

The compounds of formula (7) may be produced by Schiff's basecondensation reaction of the compound of formula (10) and H₂N-A-NH₂using the known procedure [E. J. Campbell, S. T. Nguyen, TetrahedronLett. 2001, 42, 1221.].

wherein R¹ to R⁵ and A have the same meaning as defined for formula (7).

The compounds of formula (10) may be prepared from the correspondingprecursors having at least one functional group of formula (11), formula(12) or formula (13):

wherein R¹¹, R¹², R²¹ and R²² have the same meanings as defined forformula (1) or formula (2), and X′″ is halogen or alkylsulfonato.

The functional group of formula (11) may be converted into thefunctional group of formula (1) by nucleophilic displacement of X′″ withNR¹¹R¹²R¹³ or PR¹¹R¹²R¹³. The rate of this nucleophilic displacementreaction may be enhanced by the addition of an additive such as NaI.

The functional group of formula (12) may be converted into thefunctional group of formula (1) by nucleophilic attack thereon byR¹³—X′″. Similarly, the rate of nucleophilic displacement reaction maybe enhanced by the addition of an additive such as NaI.

The functional group of formula (13) may be converted into thefunctional group of formula (2) through a reaction with ClN═PR²³R²⁴R²⁵using the known procedure [Grebe, J.; Schlecht, F.; Weller, F.; Harms,K.; Geiseler, G.; Dehnicke, K. Z. Angorg. Allg. Chem. 1999, 625, 633.].

According to another aspect of the present invention, the catalyticcomplex may be recovered by a process comprising the steps of treatingthe reaction mixture containing the polycarbonate and the complex with acomposite-forming material to form a composite of the complex and thecomposite-forming material; removing the composite from the reactionmixture containing the polycarbonate; and recovering the complex fromthe composite by treating the composite in a medium which does notdissolve the composite-forming material with an acid and/or anon-reactive metal salt, and isolating the complex released into themedium.

In the present invention, “the reaction mixture containing thepolycarbonate and the complex” is the reaction mixture obtained by theinventive polymerization process.

Preferably, the composite-forming material is an inorganic solid, apolymer or a mixture thereof, wherein the inorganic solid is selectedfrom the group consisting of silica and alumina, and the polymer has atleast one functional group capable of becoming an anion throughdeprotonation by the action of an alkoxy anion. Particularly,poly(acrylic acid) is preferable.

The composite-forming material may be preferably surface-modified ornon-modified silica or alumina.

The functional group capable of becoming an anion through deprotonationby the action of an alkoxy anion may be selected from the groupconsisting of sulfonic acid group, carboxylic acid group, phenol groupand alcohol group. Particularly, the polymer having at least onefunctional group capable of undergoing deprotonation by the action of analkoxy anion may be a copolymer or a homopolymer comprising any one offollowing units:

According to the preferable example of the present invention, thepolymer may have a number average molecular weight of from 500 to10,000,000 and it is preferably cross-linked. However, a polymer whichis not cross-linked may be used insofar as the polymer does not dissolveinto the solution containing the polycarbonate and the complex.

According to the preferable example of the present invention, thetreatment of the reaction mixture with the composite-forming materialmay be conducted by adding the composite-forming material to thereaction mixture, and the composite formed is separated from thereaction mixture by filtration; or by passing the reaction mixturethrough a column filled with the composite-forming material.

FIG. 1 shows the step of treating the reaction mixture containing thepolycarbonate and the complex with a composite-forming material to forma composite of the complex and the composite-forming material.

FIGS. 2 and 3 respectively show the process for recovering the complexfrom the composite by treating the composite of the complex and thecomposite-forming material in a medium which does not dissolve thecomposite-forming material with an acid and/or a non-reactive metal saltso that only the free complex dissolves into the medium. Preferablemedium includes methylene chloride, ethanol or methanol.

Preferably, the acid may have a Pka value of lower than that of theanion formed on the composite-forming material. An acid whose conjugatebase has a high polymerization activity is preferable. Particularly,hydrochloric acid and 2,4-dinitrophenol are preferable. Preferableexamples of the non-reactive metal salt include M′BF₄ or M′ClO₄ (whereinM′ is Li, Na or K).

Hereinafter, the present invention will be described in more detail withreference to the following examples. However, these examples are givenfor the purpose of illustration only, and are not intended to limit thescope of the invention.

EXAMPLE 1 Preparation of the complex of formula (6a)

(1) Synthesis of Compound 1

2-tent-Butylphenol (40 g, 266 mmol) was dissolved in carbon disulfide(50 mL), and bromine (42.6 g, 266 mmol) was slowly added thereto over 2hours using a dropping funnel while stirring at 0° C. After allowing thereaction to proceed for 12 hours, the solvent was removed using a rotaryvacuum evaporator. The residue was distilled under a reduced pressure at65-68° C. to obtain Compound 1 (yield: 90%).

(2) Synthesis of Compound 2

Compound 1 (2.7 g, 12 mmol) was dissolved in tetrahydrofuran (100 mL)under a nitrogen atmosphere, and tert-BuLi (14.5 g, 1.7 M pentanesolution) was added thereto using a syringe while stirring at −78° C.The reaction was allowed to proceed at −78° C. for 2 hours, andchloro(3-chloropropyl)dimethylsilane (4.639 g, 27.1 mmol) was added tothe reaction mixture using a syringe. The resulting solution was slowlywarmed to room temperature over 2 hours, 150 mL of water was addedthereto, and stirred for 4 hours. The resulting solution was extractedwith ethyl acetate. The separated organic layer was dried over anhydrousmagnesium sulfate, and filtered. The solvent was removed from thefiltrate using a rotary vacuum evaporator, and the residue was purifiedby column chromatography using a 1:20 mixture of ethyl acetate andhexane, to obtain 2-tert-butyl-4-(3-chloropropyl)dimethylsilylphenol(yield: 84%). IR (KBr): 3533 (OH) cm⁻¹. ¹H NMR (CDCl₃): δ 7.41 (s, 1H,m-H), 7.22 (dd, J=7.6 Hz, 1.2 Hz, 1H, m-H), 6.68 (d, J=7.6 Hz, 1H, o-H),4.85 (s, 1H, OH), 3.52 (t, J=7.2 Hz, 2H, CH₂Cl), 1.81 (m, 2H,CH₂CH₂CH₂), 1.45 (s, 9H, tert-BuCH₃), 0.86 (m, 2H, CH₂Si), 0.30 (s, 6H,CH₃) ppm. ¹³C {¹H} NMR (CDCl₃): δ 154.94, 135.23, 132.47, 132.09,129.12, 116.14, 48.08, 34.67, 29.68, 27.81, 13.86, −2.72 ppm. HRMS(FAB): m/z calculated ([M] C₁₅H₂₅ClOSi) 284.1363, found 284.1363.

2-tert-Butyl-4-(3-chloropropyl)dimethylsilylphenol (2.72 g, 9.90 mmol)thus obtained was dissolved in tetrahydrofuran (180 mL), and addedthereto were paraformaldehyde (1.16 g, 35.6 mmol), triethylamine (4.01g, 35.6 mmol) and magnesium chloride (3.77 g, 35.6 mmol). The resultingmixture was refluxed for 3 hours under a nitrogen atmosphere, when colorof the mixture gradually turned yellow. After the reaction wascompleted, the reaction solution was cooled to room temperature, thesolvent was removed therefrom and the resulting residue was treated withethyl acetate and water. The organic layer was separated, dried overanhydrous magnesium sulfate, and filtered. The solvent of the filtratewas removed using a rotary vacuum evaporator, and the residue waspurified by column chromatography using 1:20 mixture of ethyl acetateand hexane to obtain Compound 2. ¹H NMR (CDCl₃): δ 11.87 (s, 1H, OH),9.91 (s, 1H, CHO), 7.64 (d, J=1.6 Hz, 1H, m-H), 7.53 (d, J=1.6 Hz, 1H,m-H), 3.53 (t, J=7.2 Hz, 2H, CH₂Cl), 1.81 (m, 2H, CH₂), 1.46 (s, 9H,CH₃), 0.91 (m, 2H, CH₂Si), 0.35 (s, 6H, CH₃) ppm. ¹³C {¹H} NMR (CDCl₃):δ 197.14, 161.68, 138.35, 137.76, 137.20, 127.93, 120.34, 47.85, 34.92,29.27, 27.61, 13.49, −2.90 ppm. HRMS (FAB): m/z calculated ([M+H]⁺C₁₆H₂₆ClO₂Si) 313.1391, found 313.1391.

(3) Synthesis of Compound 3

Compound 2 (1.00 g, 3.21 mmol), tributylamine (0.891 g, 4.81 mmol) andsodium iodide (0.720 g, 4.81 mmol) were dissolved in acetonitrile (5 mL)under a nitrogen atmosphere and stirred at 90° C. for a day. Theresulting solution was cooled to room temperature, treated with waterand methylene chloride, and the organic and aqueous layers wereseparated. The aqueous layer was extracted with methylene chloride. Theabove procedure was repeated to enhance the yield of the final product.The combined organic layer was dried over anhydrous magnesium sulfateand filtered. After removing the solvent from the filtrate, diethylether was added to the resulting residue, the diethylether separate\,and diethyl ether was removed to obtain an oily material. The oil wasdissolved in ethanol, and AgBF₄ (0.686 g, 3.52 mmol) was slowly addedthereto, stirred at room temperature for 1 hour, the solvent wasremoved, and the resulting residue treated with methylene chloride (10mL) and water (10 mL). The organic layer was separated, dried overanhydrous magnesium sulfate, and filtered. The solvent was removed fromthe filtrate, and the residue was purified by column chromatography(methylene chloride:ethanol=10:1) to obtain Compound 3 (yield: 56%). ¹HNMR (CDCl₃): δ 11.92 (s, 1H, OH), 9.96 (s, 1H, CHO), 7.67 (s, 1H, m-H),7.59 (s, 1H, m-H), 3.24-3.08 (m, 8H, NCH₂), 1.79-1.50 (m, 8H, CH₂), 1.42(s, 9H, CH₃), 1.43-1.30 (m, 6H, CH₂), 1.04-0.86 (m, 9H, CH₃), 0.72-0.78(t, J=8.4 Hz, 2H, CH₂Si), 0.34 (s, 6H, CH₃Si) ppm. ¹³C {¹H} NMR (CDCl₃):δ 198.12, 161.73, 138.39, 138.08, 137.18, 127.04, 120.49, 61.10, 58.29,34.90, 29.25, 23.75, 19.59, 16.69, 13.59, 12.23, −3.15 ppm. FIRMS (FAB):m/z calculated ([M-BF₄ ⁻]⁺C₂₈H₅₂NO₂Si) 462.3762, found 462.3767.

(4) Synthesis of Compound 4

Compound 3 (0.212 g, 0.368 mmol) and trans-1,2-diaminocyclohexane (0.20g, 0.18 mmol) were dissolved in ethanel (2 mL) under a nitrogenatmosphere, molecular sieve was added thereto, and stirred at roomtemperature for 10 hours. The solvent was removed to obtain a yellowsolid, which was purified by column chromatography (methylenechloride:ethanol=10:1) to obtain Compound 4. IR (KBr): 3421 (OH), 1625(C═N) cm⁻¹. ¹H NMR (CDCl₃): δ 14.16 (s, 2H, OH), 8.42 (s, 2H, CH═N),7.32 (s, 2H, m-H), 7.21 (s, 2H, m-H), 3.40 (t, J=4.0 Hz, 2H, CHN), 3.11(t, J=8.0 Hz, 16H, NCH₂), 2.04-1.96 (m, 2H, cyclohexyl-CH₂), 1.92-1.87(m, 2H, cyclohexyl-CH₂), 1.74-1.68 (m, 4H, cyclohexyl-CH₂), 1.58-1.40(m, 16H, NCH₂CH₂), 1.41 (s, 18H, tert-BuCH₃) 1.32 (sextet, J=7.2 Hz,12H, NCH₂CH₂CH₂), 0.90 (t, J=7.6 Hz, 18H, CH₃), 0.70 (t, J=8.0 Hz, 4H,SiCH₂), 0.26 (s, 6H, SiCH₃), 0.25 (s, 6H, SiCH₃) ppm. ¹³C {¹H} NMR(CDCl₃): δ165.35, 161.39, 136.34, 135.68, 133.46, 124.69, 118.48, 71.70,60.95, 58.21, 34.81, 32.73, 29.38, 24.03, 23.65, 19.53, 16.72, 13.54,12.24, −2.94, −3.22 ppm. HRMS (FAB): m/z calculated ([M-BF₄]⁺C₆₂H₁₁₄N₄O₂Si₂BF₄) 1089.8504, found 1089.8521.

(5) Synthesis of Compound 5

Upon dissolving Co(OAc)₂ (0.022 g, 0.13 mmol)) and Compound 4 (0.147 g,0.125 mmol) in ethanol (6 mL) under a nitrogen atmosphere, a red solidwas formed while the color of the solvent changed to red. After furtherstirring for 2 hours, the red solid was filtered, washed twice withethanol (2 mL), and dried in a vacuum. The resulting solid and2,4-dinitrophenol (23 g, 0.125 mmol) were dissolved in methylenechloride and stirred for 1.5 hours under an oxygen atmosphere. Sodium2,4-dinitrophenoxide (0.051 g, 0.25 mmol) was added thereto, and stirredovernight. The resulting solution was filtered through cellite, and thesolvent was removed from the filtrate to obtain Compound 5 as a solid.¹H NMR (dmso-d₆): δ 8.58 (d, J=0.8 Hz, 3H, (NO₂)₂C₆H₃O), 7.90 (s, 2H,CH═N), 7.75 (dd, J=9.6, 3.2 Hz, 3H, (NO₂)₂C₆H₃O), 7.68 (s, 2H, m-H),7.45 (s, 2H, m-H), 6.30 (d, J=9.6, 3H, (NO₂)₂C₆H₃O), 3.63-3.57 (br, 2H,cyclohexyl-CH), 3.23-3.12 (m, 12H, NCH₂), 3.12-3.02 (m, 4H, NCH₂),2.08-1.96 (br, 4H, cyclohexyl-CH₂), 1.96-1.82 (br, 4H, cyclohexyl-CH₂),1.74 (s, 18H, CH₃) 1.70-1.52 (m, 12H, butyl-CH₂), 1.36-1.25 (m, 12H,butyl-CH₂), 0.92 (t, J=7.6 Hz, 18H, CH₃), 0.71 (t, J=8.0, 4H, SiCH₂),0.30 (s, 3H, SiCH₃), 0.29 (s, 3H, SiCH₃) ppm. ¹³C {¹H} NMR (dmso-d₆): δ169.79, 164.93, 164.40, 141.64, 140.23, 134.89, 127.07, 126.15, 124.70,120.92, 119.15, 69.30, 60.34, 57.39, 35.55, 30.25, 29.51, 24.18, 23.02,19.17, 16.32, 13.43, 11.91, −2.66, −2.74 ppm. HRMS (FAB): m/z calculated([M-2{(NO₂)₂C₆H₃O}]⁺ C₆₈H₁₁₅CoN₆O₇Si₂) 1242.7687, found 1242.7698.

EXAMPLE 2 Preparation of the Complex of Formula (6b)

(1) Synthesis of Compound 6

Compound 6 was synthesized from Compound 3 by using the known procedure[T. V. Hansen, L. Skatteböl, Tetrahedron Lett. 2005, 46, 3829]. Theresulting product was purified by column chromatography using a 40:1mixture of methylene chloride and ethanol to obtain Compound 6. IR(KBr): 3409 (OH), 1627 (C═N) cm⁻¹. ¹H NMR (CDCl₃): δ 14.16 (s, 1H, OH),13.62 (s, 1H, OH), 8.36 (s, 1H, CH═N), 8.32 (s, 1H, CH═N), 7.30 (d,J=2.4 Hz, 1H, m-H), 7.29 (d, J=1.6 Hz, 1H, m-H), 7.16 (d, J=1.6 Hz, 1H,m-H), 6.99 (d, J=2.4 Hz, 1H, m-H), 3.42-3.32 (m, 2H, CHN), 3.30 (t,J=8.4 Hz, 8H, NCH₂), 2.13-1.56 (m, 8H, cyclohexyl-CH₂), 1.68-1.55 (m,8H, NCH₂CH₂), 1.41 (s, 9H, tert-BuCH₃), 1.40 (s, 9H, tert-BuCH₃),1.39-1.34 (m, 6H, NCH₂CH₂CH₂), 1.24 (s, 9H, tert-BuCH₃), 0.93 (t, J=7.2Hz, 9H, CH₃), 0.77-0.71 (m, 2H, SiCH₂), 0.27 (s, 3H, SiCH₃), 0.25 (s,3H, SiCH₃) ppm. ¹³C {¹H} NMR (CDCl₃): δ 165.45, 165.08, 161.48, 157.67,139.73, 136.54, 136.08, 135.57, 133.36, 126.58, 125.83, 124.51, 118.49,117.63, 72.43, 72.14, 61.64, 59.03, 34.99, 34.84, 34.08, 33.31, 31.45,29.47, 29.40, 24.34, 24.22, 19.80, 17.24, 13.72, 12.67, −2.88, −2.98ppm. HRMS (FAB): m/z calculated ([M-BF₄ ⁻]⁺ C₄₉H₈₄N₃O₂Si) 774.6327,found 774.6333.

(2) Synthesis of Compound 7

The procedure for synthesizing Compound 5 was repeated except thatCompound 6 was used instead of Compound 4 to obtain Compound 7. ¹H NMR(dmso-d₆): δ 8.69 (br, 2H, (NO₂)₂C₆H₃O), 7.88 (s, 2H, CH═N), 7.81 (br,2H, (NO₂)₂C₆H₃O), 7.69 (s, 1H, m-H), 7.47 (s, 1H, m-H), 7.45 (s, 2H,m-H), 6.36 (br, 2H, (NO₂)₂C₆H₃O), 3.65-3.59 (m, 2H, CHN), 3.26-3.14 (m,6H, NCH₂), 3.12-3.04 (m, 2H, NCH₂), 2.08-1.96 (m, 4H, cyclohexyl-CH₂),1.96-1.82 (m, 4H, cyclohexyl-CH₂), 1.76 (s, 9H, tert-BuCH₃), 1.74 (s,9H, tert-BuCH₃), 1.65-1.52 (m, 8H, NCH₂CH₂), 1.31 (s, 9H, tert-BuCH₃),1.32-1.26 (m, 6H, NCH₂CH₂CH₂), 0.92 (t, J=7.2 Hz, 9H, CH₃), 0.72 (t,J=8.0 Hz, 2H, SiCH₂), 0.30 (s, 6H, SiCH₃) ppm. ¹³C {¹H} NMR (dmso-d₆):δ171.30, 164.92, 164.25, 164.03, 163.73, 161.46, 141.53, 141.38, 140.01,135.63, 134.57, 128.84, 128.52, 127.28, 124.84, 120.54, 119.12, 118.15,69.12, 69.05, 60.24, 59.69, 57.28, 35.58, 35.40, 33.33, 31.24, 30.22,30.10, 29.35, 28.46, 24.07, 22.89, 19.04, 16.20, 13.88, 13.28, 11.81,−0.05, −2.80, −2.85 ppm. HRMS (FAB): m/z calculated ([M−{(NO₂)₂C₆H₃O}]⁺C₄₉H₈₂CoN₃O₂Si) 831.5503, found 831.5508.

EXAMPLE 3 Preparation of the Complex of Formula (6c)

(1) Synthesis of Compound 8

Compound 1 (15 g, 65.5 mmol), dihydropyran (6.33 g, 75.3 mmol) andpyridinium p-toluenesulfonate (0.200 g) were dissolved in methylenechloride under a nitrogen atmosphere. The solution was stirred at roomtemperature for 19 hours. The solvent was removed and the residue wasrecrystallized with hexane to obtain Compound 8 as a white solid (yield:72%).

(2) Synthesis of Compound 9

Compound 8 (14.6 g, 46.7 mmol) was dissolved in tetrahydrofuran (300 mL)at −78° C. under a nitrogen atmosphere, and n-BuLi (14.23 g, 51.34 mmol,2.5 M hexane solution) was added thereto using a syringe. The reactionwas allowed to proceed for 2 hours while stirring, andchlorodiphenylphosphine (10.3 g, 46.7 mmol) was added to the reactionmixture using a syringe. The resulting solution was slowly warmed toroom temperature while stirring over 2 hours. The resulting solution wastreated with ethyl acetate (100 mL) and water (100 mL). The organiclayer was separated, dried over anhydrous magnesium sulfate, andfiltered. The solvent was removed from the filtrate, and the residue wasrecrystallized with hexane to obtain Compound 9 as a solid (yield: 80%).¹H NMR (CDCl₃): δ 7.39 (s, 1H), 7.37 (s, 1H), 7.35 (s, 9H, Ph), 7.19 (d,²J_(PH)=8.0 Hz, 1H, m-H), 7.11 (dd, ²J_(PH)=8.0 Hz, J_(HH)=6.8 Hz, 1H),5.53 (br, 1H, THP), 3.93 (td, J=10.0 Hz, 2.4 Hz, 1H, THP), 3.72-3.65 (m,1H, THP), 2.15-2.02 (m, 1H, THP), 2.92-1.90 (m, 2H, THP), 1.83-1.71 (m,2H, THP), 1.71-1.62 (m, 1H, THP), 1.41 (s, 9H, tert-BuCH₃) ppm. ¹³C {¹H}NMR (CDCl₃): δ 156.59, 138.02 (d, ³J_(CP)=3.8 Hz, m-Ph), 137.92 (d,³J_(CP)=3.7 Hz, m-Ph), 137.71 (d, ¹J_(CP)=9.1 Hz, PC), 133.29 (d,²J_(CP)=18.2 Hz, o-Ph), 133.28 (d, ²J_(CP)=18.9 Hz, o-Ph), 133.00,132.79 (d, ²J_(CP)=12.1 Hz, m-C), 128.19, 128.16 (d, ²J_(CP)=6.8 Hz,m-C), 127.19 (d, ³J_(CP)=6.0 Hz, o-C), 114.32 (d, ³J_(CP)=5.8 Hz, o-C),61.89, 35.04, 30.57, 29.96, 25.31, 19.01 ppm. ³¹P NMR (CDCl₃): δ 11.53ppm. Anal. Calc. (C₂₇H₃₁O₂P): C, 77.49; H, 7.47%. found: C, 77.68; H,7.60%.

The resulting solid (15.60 g, 37.28 mmol) and pyridium p-toluenesulfonate (9.36 g, 37.28 mmol) were dissolved in a mixture oftetrahydrofuran (60 mL) and ethanol (40 mL), and the resulting mixturewas stirred at 80-90° C. overnight. The reaction solution was treatedwith sodium hydrogen carbonate and ethyl acetate. The organic layer wasseparated, dried over anhydrous magnesium sulfate, and filtered. Thesolvent was removed from the filtrate, and purified by columnchromatography to obtain 2-tert-butyl-4-diphenylphosphanylphenol. IR(KBr): 3307 (OH) cm⁻¹. ¹H NMR (CDCl₃): δ 7.41 (dd, ²J_(PH)=9.2 Hz,J_(HH)=1.6 Hz, 1H, m-H), 7.40-7.34 (m, 10H, Ph), 7.04 (ddd, ²J_(PH)=9.2Hz, J_(HH)=7.6 Hz, 1.6 Hz, 1H, m-H), 6.69 (d, J=7.6 Hz, 1H, o-H), 5.27(s, 1H, OH), 1.42 (s, 9H, tert-BuCH₃) ppm. ¹³C {¹H}NMR (CDCl₃): δ155.06, 137.76 (d, ¹J_(CP)=9.8 Hz, PC), 136.08 (d, ¹J_(CP)=9.1 Hz, PC),133.55 (d, ²J_(CP)=28 Hz, m-C), 133.21 (d, ²J_(CP)=18 Hz, o-Ph), 132.68(d, ²J_(CP)=28 Hz, m-C), 128.28, 128.20 (d, ³J_(CP)=6.9 Hz, m-Ph),126.64 (d, ³J_(CP)=6.1 Hz, o-C), 116.91 (d, ³J_(CP)=6.1 Hz, o-C), 34.73,29.53 ppm. ³¹P NMR (CDCl₃): δ 11.44 ppm. Anal. Calc. (C₂₂H₂₃OP): C,79.02; H, 6.93; O, 4.78; P, 9.26%. found: C, 79.29; H, 7.05%.

The procedure for synthesizing Compound 2 was repeated except that2-tert-butyl-4-diphenylphosphanylphenol was used instead of2-tert-butyl-4-(3-chloropropyl)dimethylsilylphenol, to obtain Compound9. IR (KBr): 3390 (OH), 1649 (C═O) cm⁻¹. ¹H NMR (CDCl₃): δ 11.87 (s, 1H,OH), 9.70 (s, 1H, CHO), 7.51 (d, ²J_(PH)=8.4 Hz, 1H, m-H), 7.40-7.20 (m,11H, P-Ph), 1.34 (s, 9H, tert-BuCH₃) ppm. ¹³C {¹H}NMR (CDCl₃): δ 196.85,161.64, 139.44 (d, ²J_(CP)=24.3 Hz, m-C), 138.38 (d, ³J_(CP)=6.8 Hz,o-C), 137.67 (d, ²J_(CP)=18.2 Hz, m-C), 136.90 (d, ¹J_(CP)=10.6 Hz,C—P), 133.20 (d, ²J_(CP)=19 Hz, o-Ph), 128.66, 128.43 (d, ³J_(CP)=6.1Hz, m-Ph), 126.50 (d, ¹J_(CP)=10.6 Hz, C—P), 120.73 (d, ³J_(CP)=6.1 Hz,o-C), 35.06, 29.16 ppm. ³¹P NMR (CDCl₃): δ 10.99 ppm. Anal. Calc.(C₂₃H₂₃O₂P): C, 76.23; H, 6.40; O, 8.83; P, 8.55%. found: C, 76.03; H,6.08%.

(3) Synthesis of Compound 10

Compound 10 was synthesized from Compound 9 by using the known procedure[T. V. Hansen, L. Skatteböl, Tetrahedron Lett. 2005, 46, 3829.]. IR(KBr): 3407 (OH), 1627 (C═N) cm⁻¹. ¹H NMR (C₆D₆): δ 14.61 (s, 1H, OH),13.96 (s, 1H, OH), 7.90 (s, 1H, CH═N), 7.64 (dd, J_(HH)=8.8 Hz,²J_(PH)=1.6 Hz, 1H, m-H), 7.58 (s, 1H, CH═N), 7.51 (d, J_(HH)=2.4 Hz,1H), 7.46-7.35 (m, 4H, Ph), 7.14-7.04 (m, 7H, Ph), 6.97 (d, J=2.4 Hz,1H, m-H), 2.91-2.82 (m, 1H, NCH), 2.74-2.67 (m, 1H, NCH), 1.69-1.62 (br,2H, cyclohexyl-CH₂), 1.62 (s, 9H, tert-BuCH₃), 1.54-1.50 (br, 2H,cyclohexyl-CH₂), 1.47 (s, 9H, tert-BuCH₃), 1.37-1.31 (br, 2H,cyclohexyl-CH₂), 1.29 (s, 9H, tert-BuCH₃), 1.16-1.08 (br, 2H,cyclohexyl-CH₂) ppm. ¹³C {¹H} NMR (CDCl₃): δ 166.31, 165.78, 161.98,158.59, 140.06, 138.91 (d, ²J_(CP)=19.7 Hz), 138.79 (d, ²J_(CP)=19.7Hz), 137.98 (d, ¹J_(CP)=8.3 Hz), 136.79, 136.49, 136.20 (d, ²J_(CP)=24.3Hz), 135.80, 133.90 (d, ¹J_(CP)=8.3 Hz), 133.70 (d, ³J_(PC)=7.6 Hz),128.79 (d, ³J_(CP)=3.7 Hz), 128.73 (d, ³J_(CP)=3.0 Hz), 128.60 (d,J_(CP)=8.4 Hz), 127.02, 126.44, 125.04 (d, J_(CP)=8.3 Hz), 119.54 (d,³J_(CP)=6.8 Hz), 118.41, 72.22, 71.55, 35.52, 35.41, 34.38, 33.07,32.97, 31.86, 29.94, 29.66, 24.56 ppm. ³¹P NMR (CDCl₃): δ 11.66 ppm.Anal. Calc. (C₄₄H₅₅N₂O₂P): C, 78.30; H, 8.21; N, 4.15; O, 4.74; P,4.59%. found: C, 78.51; H, 8.32%.

(4) Synthesis of Compound 11

Compound 11 was synthesized from Compound 10 by using the procedure. [J.Grebe, F. Schlecht, F. Weller, K. Harms, G. Geiseler, K. Dehnicke, Z.Angorg. Allg. Chem. 1999, 625, 633.] (yield: 79%). IR (KBr): 3367 (OH),1629 (C═N) cm⁻¹. ¹H NMR (CDCl₃): δ 15.16 (s, 1H, OH), 13.48 (s, 1H, OH),8.39 (s, 1H, CH═N), 8.09 (s, 1H, CH═N), 7.67-7.61 (m, 2H), 7.60-7.52 (m,4H), 7.52-7.38 (m, 19H), 7.34 (d, J=2.4 Hz, 1H), 7.31 (dd, J=13.2 Hz,J=2.0 Hz, 1H), 7.06 (d, J=2.0 Hz, 1H), 6.81 (dd, J=13.2 Hz, J=1.6 Hz,1H), 3.42-3.38 (m, 2H, CHN), 2.02-1.88 (m, 6H, cyclohexyl-CH₂), 1.73(br, 2H, cyclohexyl-CH₂), 1.37 (s, 9H, tert-BuCH₃), 1.27 (s, 9H,tert-BuCH₃), 1.18 (s, 9H, tert-BuCH₃) ppm. ¹³C {¹H} NMR (CDCl₃): δ167.32, 165.95, 164.16, 157.98, 140.40, 140.19 (d, J_(CP)=12.1 Hz),136.71, 135.56 (d, J_(CP)=13.6 Hz), 133.90, 132.11 (d, J_(CP)=10.6 Hz),131.97 (d, J_(CP)=3.0 Hz), 131.76 (d, J_(CP)=12.1 Hz), 129.65 (d,J_(CP)=12.8 Hz), 128.19 (d, J_(CP)=9.1 Hz), 127.80, 127.06, 126.74,126.20, 118.36 (d, J_(CP)=15.1 Hz), 117.92, 113.31, 112.19, 72.78,71.44, 35.45, 35.34, 34.48, 33.65, 33.59, 31.80, 29.76, 29.18, 24.58,24.51 ppm. ³¹P NMR (CDCl₃): 38.81 (d, J_(PP)=55.0 Hz), 33.80 (d,J_(PP)=55.0 Hz) ppm. HRMS (FAB): m/z calculated ([M-Cl]⁺ C₆₂H₇₀N₃O₂P₂)950.4938, found 950.4943.

(5) Synthesis of Compound 12

Compound 11 (0.046 g, 0.047 mmol) and AgBF₄ (0.011 g, 0.56 mmol) wereadded in ethanol and stirred at room temperature overnight. Theresulting solution was filtered through cellite, and the solvent wasremoved from the filtrate. The procedure for synthesizing Compound 5 wasrepeated to obtain Compound 12. ¹H NMR (dmso-d₆): δ 8.80 (br, 2H,(NO₂)₂C₆H₃O), 7.91-7.40 (m, 32H), 6.80 (s, 1H), 6.51 (br, 2H,(NO₂)₂C₆H₃O), 3.06 (d, J=9.2 Hz, 1H, CHN), 2.93 (d, J=9.2 Hz, 1H, CHN),1.98-1.80 (m, 6H, cyclohexyl-CH₂), 1.73 (s, 9H, tert-BuCH₃), 1.41-1.48(m, 2H, cyclohexyl-CH₂), 1.49 (s, 9H, tert-BuCH₃), 1.29 (s, 9H,tert-BuCH₃) ppm. ¹³C {¹H} 172.39, 169.37, 165.70, 165.50, 162.12, 144.24(d, J_(CP)=11.4 Hz), 142.35, 141.00, 137.05, 135.22 (d, J_(CP)=2.2 Hz),134.16, 133.88, 133.28 (d, J_(CP)=11.3 Hz), 132.58 (d, J_(CP)=11.4 Hz),132.49, 132.36, 130.38 (d, J_(CP)=12.9 Hz), 130.05 (d, J_(CP)=12.9 Hz),129.29, 128.39, 127.37, 126.03, 124.34, 123.32, 120.93 (d, J_(CP)=15.1Hz), 118.88, 109.57, 108.44, 70.58, 70.26, 36.63, 36.60, 34.43, 32.20,31.22, 30.57, 30.33, 29.50, 24.99, 21.95 ppm. ¹P NMR (dmso-d₆): δ 42.2,41.89 ppm. HRMS (FAB): m/z calculated ([M-{(NO₂)₂C₆H₃O}]⁺C₆₂H₆₈CoN₃O₂P₂) 1007.4113, found 1007.4119.

EXAMPLE 4 Preparation of the Complex of Formula (6d)

(1) Synthesis of Compound 13

AlCl₃ (1.47 g, 11.01 mmol) and 4-chlorobutyryl chloride (1.04 g, 7.34mmol) were dissolved in methylene chloride under a nitrogen chlorideatmosphere. 2-Isopropylphenol (1.00 g, 7.34 mmol) was slowly addedthereto at 20° C. over 30 minutes, stirred for 3 hours, and 2 N HCl wasadded thereto. The resulting solution was treated with methylenechloride and water. The organic layer was separated, dried overanhydrous magnesium sulfate, and filtered. The solvent was removed fromthe filtrate, the residue was dissolved in methanol (10 mL), and sodiumhydrogen carbonate was added thereto. The solvent was removed using arotary vacuum evaporator, and the residue was purified by columnchromatography to obtain Compound 13 (yield: 63%). ¹H NMR (CDCl₃): δ7.91 (d, J=2.0 Hz, 1H, m-H), 7.50 (dd, J=8.4, 2.0 Hz, 1H, m-H), 6.86 (d,J=8.4 Hz, 1H, o-H), 6.12 (s, 1H, OH), 3.69 (t, J=6.4 Hz, 2H, —CH₂Cl),3.29 (septet, J=6.8 Hz, 1H, iPr—CH), 3.18 (t, J=6.8 Hz, 2H, —CH₂), 2.25(quintet, J=6.4 Hz, 2H, —CH₂—), 1.30 (d, J=8.4 Hz, 6H, iPr—CH₃) ppm. ¹³C{¹H} NMR (CDCl₃): δ198.77, 158.00, 134.87, 129.50, 127.87, 127.17,115.06, 44.81, 35.06, 27.29, 27.14, 22.44 ppm.

(2) Synthesis of Compound 14

The procedure for synthesizing Compound 13 was repeated except that2-methylphenol was used instead of isopropylphenol to obtain Compound14. ¹H NMR (CDCl₃): δ 7.82 (d, J=2.0 Hz, 1H, m-H), 7.77 (dd, J=8.0, 2.0Hz, 1H, m-H), 6.90 (s, 1H, OH), 6.88 (d, J=8.0 Hz, 1H, o-H), 3.68 (t,J=6.4 Hz, 2H, —CH₂Cl), 3.17 (t, J=6.4 Hz, 2H, —CH₂), 2.32 (s, 3H, —CH₃),2.24 (quintet, J=6.4 Hz, 2H, —CH₂) ppm. ¹³C {¹H} NMR (CDCl₃): δ 198.81,159.04, 131.56, 129.13, 128.17, 124.37, 114.71, 44.79, 35.10, 27.17,16.00 ppm.

(3) Synthesis of Compound 15

The procedure for synthesizing Compound 13 was repeated except that2-tert-butylphenol was used instead of isopropylphenol to obtainCompound 15. ¹H NMR (CDCl₃): δ 7.99 (d, J=2.0 Hz, 1H, m-H), 7.76 (dd,J=8.4, 2.0 Hz, 1H, m-H), 6.81 (d, J=8.4 Hz, 1H, o-H), 6.70 (s, 1H, OH),3.69 (t, J=6.4 Hz, 2H, —CH₂Cl), 3.17 (t, J=7.2 Hz, 2H, —CH₂), 2.25(quintet, J=6.0 Hz, 2H, —CH₂—), 1.45 (s, 9H, —C(CH₃)₃), ppm. ¹³C {¹H}NMR(CDCl₃): δ 198.83, 159.54, 136.28, 128.93, 128.16, 127.78, 116.27,44.97, 34.97, 34.83, 29.38, 27.26 ppm.

(4) Synthesis of Compound 16

Compound 13 (1.80 g, 7.47 mmol) was dissolved in ethanol (7 mL), and 10%Pd on activated charcoal (64 mg) was added thereto. The resultingsolution was hydrogenated overnight at room temperature under theambient pressure. The resulting mixture was filtered through cellite,and the solvent was removed from the filtrate using a rotary vacuumevaporator to obtain a bright brown sold (yield: 100%). ¹H NMR (CDCl₃):δ 7.00 (d, J=7.6 Hz, 1H, m-H), 6.88 (dd, J=8.0, 2.0 Hz, 1H, m-H), 6.68(d, J=8 Hz, 1H, o-H), 4.73 (s, 1H, OH), 3.58 (t, J=6.8 Hz, 2H, CH₂Cl),3.22 (septet, J=6.8 Hz, 1H, iPr—CH), 2.60 (t, J=6.8 Hz, 2H, CH₂),1.88-1.72 (m, 4H, —CH₂CH₂—), 1.30 (d, J=6.8 Hz, 6H, iPr—CH₃) ppm. ¹³C{¹H} NMR (CDCl₃): δ 150.67, 134.15, 133.91, 126.16, 126.08, 115.03,45.01, 34.56, 32.21, 28.94, 27.08, 22.70 ppm.

The bright brown solid was formylated using the same procedure employedfor synthesizing Compound 2 to obtain Compound 16 (yield: 64%). ¹H NMR(CDCl₃): δ 11.22 (s, 1H, OH), 9.85 (s, 1H, CHO), 7.28 (d, J=1.6 Hz, 1H,m-H), 7.19 (d, J=2.4 Hz, 1H, m-H), 3.59 (t, J=6.0 Hz, 2H, CH₂Cl), 3.37(septet, J=6.8 Hz, 1H, iPr—CH), 2.65 (t, J=6.8 Hz, 2H, CH₂), 1.88-1.77(m, 4H, —CH₂CH₂—), 1.27 (d, J=6.8 Hz, 6H, iPr—CH₃) ppm. ¹³C {¹H} NMR(CDCl₃): δ 196.52, 157.32, 136.88, 133.88, 132.67, 130.09, 119.78,44.87, 34.26, 32.07, 28.66, 26.38, 22.39 ppm.

(5) Synthesis of Compound 17

The procedure for synthesizing Compound 16 was repeated except thatCompound 14 was used instead of compound 13 to obtain Compound 17. ¹HNMR (CDCl₃): δ 6.96 (s, 1H, m-H), 6.90 (dd, J=8.0, 2.0 Hz, 1H, m-H),6.71 (d, J=8 Hz, 1H, o-H), 4.82 (s, 1H, OH), 3.58 (t, J=6.4 Hz, 2H,—CH₂Cl), 2.58 (t, J=7.2 Hz, 2H, —CH₂), 2.27 (s, 3H, —CH₃), 1.87-1.72 (m,4H, —CH₂CH₂—) ppm. ¹³C {¹H} NMR (CDCl₃): δ 151.61, 133.84, 130.79,126.62, 123.41, 114.62, 45.08, 34.23, 32.11, 28.93, 15.91 ppm.

(6) Synthesis of Compound 18

The procedure for synthesizing Compound 16 was repeated except thatCompound 15 was used instead of Compound 13 to obtain Compound 18. ¹HNMR (CDCl₃): δ 7.08 (d, J=2.4 Hz, 1H, m-H), 6.90 (dd, J=8.0, 2.4 Hz, 1H,m-H), 6.62 (d, J=8 Hz, 1H, o-H), 5.00 (s, 1H, OH), 3.59 (t, J=6.4 Hz,2H, —CH₂Cl), 2.60 (t, J=7.2 Hz, 2H, —CH₂), 1.90-1.72 (m, 4H, —CH₂CH₂—),1.45 (s, 9H, —C(CH₃)₃) ppm. ¹³C {¹H} NMR (CDCl₃): δ 152.17, 135.72,133.40, 126.92, 126.29, 115.25, 45.06, 34.65, 34.55, 32.27, 29.68, 28.99ppm.

(7) Synthesis of Compound 19

The procedure for synthesizing Compound 3 was repeated except thatCompound 16 was used instead of Compound 2 and the reaction was allowedto proceed for 2 days to obtain Compound 19 (yield: 98%). ¹H NMR(CDCl₃): δ 11.24 (s, 1H, OH), 9.86 (s, 1H, CHO), 7.32 (d, J=2.0 Hz, 1H,m-H), 7.27 (s, J=2.4 Hz, 1H, m-H), 3.32 (septet, J=6.8 Hz, 1H, iPr—CH),3.26-3.06 (m, 8H, —NCH₂), 2.67 (t, J=6.8 Hz, 2H, CH₂), 1.76-1.66 (m, 6H,CH₂) 1.62-1.52 (m, 6H, CH₂), 1.44-1.32 (m, 6H, CH₂), 1.23 (d, J=6.8 Hz,6H, iPr—CH₃), 0.95 (t, J=7.6 Hz, 9H, CH₃) ppm. ¹³C {¹H} NMR (CDCl₃): δ197.18, 157.30, 136.76, 133.81, 131.86, 130.75, 119.82, 58.37, 33.82,27.68, 26.38, 25.59, 23.75, 22.33, 21.00, 19.90, 19.60, 13.59 ppm.

(8) Synthesis of Compound 20

The procedure for synthesizing Compound 19 was repeated except thatCompound 17 was used instead of Compound 16 to obtain Compound 20. ¹HNMR (CDCl₃): δ 11.13 (s, 1H, OH), 9.85 (s, 1H, CHO), 7.31 (d, J=2.0 Hz,1H, m-H), 7.24 (s, J=2.4 Hz, 1H, m-H), 3.24-3.09 (m, 8H, —NCH₂), 2.66(t, J=6.8 Hz, 2H, CH₂), 2.24 (S, 3H, —CH₃), 1.74-1.68 (m, 6H, CH₂)1.61-1.53 (m, 6H, CH₂), 1.44-1.32 (m, 6H, CH₂), 0.96 (t, J=7.6 Hz, 9H,CH₃) ppm. ¹³C {¹H} NMR (CDCl₃): δ 196.99, 158.05, 138.10, 131.69,130.84, 126.52, 119.67, 58.40, 33.48, 27.62, 23.77, 20.83, 19.89, 19.62,15.07, 13.60 ppm.

(9) Synthesis of Compound 21

The procedure for synthesizing Compound 19 was repeated except thatCompound 18 was used instead of Compound 16 to obtain Compound 21. ¹HNMR (CDCl₃): δ 11.67 (s, 1H, OH), 9.86 (s, 1H, CHO), 7.34 (d, J=2.0 Hz,1H, m-H), 7.32 (s, J=2.4 Hz, 1H, m-H), 3.23-3.08 (m, 8H, —NCH₂), 2.69(t, J=6.8 Hz, 2H, CH₂), 1.76-1.68 (m, 6H, CH₂), 1.63-1.55 (m, 6H, CH₂),1.41 (s, 9H, —C(CH₃)₃), 1.44-1.35 (m, 6H, CH₂), 0.98 (t, J=7.6 Hz, 9H,CH₃) ppm. ¹³C {¹H}NMR (CDCl₃): δ 197.42, 159.29, 137.96, 134.33, 131.30,120.31, 58.43, 34.84, 33.95, 29.29, 27.71, 23.80, 21.09, 19.91, 19.64,13.62 ppm.

(10) Synthesis of Compound 22

The procedure for synthesizing Compound 4 was repeated except thatCompound 19 was used instead of Compound 3 to obtain Compound 22. ¹H NMR(CDCl₃): δ 8.24 (s, 1H, CHO), 7.02 (d, J=1.6 Hz, 1H, m-H), 6.80 (s,J=1.6 Hz, 1H, m-H), 3.32 (septet, J=6.8 Hz, 1H, iPr—CH), 3.06-3.20 (m,8H, NCH₂), 2.55 (t, J=6.8 Hz, 2H, CH₂), 2.02-1.92 (m, 2H,cyclohexyl-CH₂), 1.90-1.84 (m, 2H, cyclohexyl-CH₂), 1.66-1.56 (m, 6H,butyl-CH₂) 1.55-1.44 (m, 6H, butyl-CH₂), 1.39-1.27 (m, 4H, CH₂), 1.23(d, J=5.2 Hz, 3H, iPr—CH₃), 1.21 (d, J=5.2 Hz, 3H, iPr—CH₃), 0.90 (t,J=7.6 Hz, 9H, butyl-CH₃) ppm. ¹³C {¹H} NMR (CDCl₃): δ 164.91, 156.53,135.77, 130.28, 128.81, 128.39, 117.67, 72.18, 58.31, 33.99, 32.96,27.85, 26.51, 24.15, 23.68, 22.65, 22.52, 20.99, 19.55, 13.61, 13.55ppm.

(11) Synthesis of Compound 23

The procedure for synthesizing Compound 22 was repeated except thatCompound 20 was used instead of Compound 19 to obtain Compound 23. ¹HNMR (CDCl₃): δ 8.20 (s, 1H, CHO), 6.96 (d, J=1.6 Hz, 1H, m-H), 6.79 (s,J=1.6 Hz, 1H, m-H), 3.31-3.28 (m, 1H, cyclohexyl-CH), 3.10-3.06 (m, 8H,NCH₂), 2.52 (t, J=6.8 Hz, 2H, CH₂), 2.18 (s, 3H, —CH₃), 1.93-1.90 (m,2H, cyclohexyl-CH₂), 1.87-1.84 (m, 2H, cyclohexyl-CH₂), 1.73-1.50 (m,16H, —CH₂), 1.35-1.26 (m, 8H, —CH₂), 0.88 (t, J=7.6 Hz, 9H, butyl-CH₃)ppm. ¹³C {¹H} NMR (CDCl₃): δ 164.52, 157.38, 133.26, 130.15, 128.51,125.36, 117.52, 72.38, 58.30, 33.58, 33.10, 27.80, 24.15, 23.67, 20.75,19.89, 19.54, 15.55, 13.55 ppm.

(12) Synthesis of Compound 24

The procedure for synthesizing Compound 22 was repeated except thatCompound 21 was used instead of Compound 19 to obtain Compound 24. ¹HNMR (CDCl₃): δ 8.23 (s, 1H, CHO), 7.04 (d, J=1.6 Hz, 1H, m-H), 6.79 (s,J=1.6 Hz, 1H, m-H), 3.33-3.31 (m, 1H, cyclohexyl-CH), 3.14-3.07 (m, 8H,NCH₂), 2.53 (t, J=6.8 Hz, 2H, CH₂), 2.00-1.97 (m, 2H, cyclohexyl-CH₂),1.89-1.86 (m, 2H, cyclohexyl-CH₂), 1.70-1.49 (m, 16H, —CH₂), 1.40 (s,9H, —C(CH₃)₃), 1.38-1.29 (m, 8H, —CH₂), 0.90 (t, J=7.6 Hz, 9H,butyl-CH₃) ppm. ¹³C {¹H} NMR (CDCl₃): δ 165.25, 158.32, 136.76, 129.56,129.22, 128.97, 118.19, 71.97, 58.27, 34.72, 34.06, 32.94, 29.46, 27.81,24.22, 23.66, 21.00, 19.88, 19.53, 13.52 ppm.

(13) Synthesis of Compound 25

The procedure for synthesizing Compound 5 was repeated except thatCompound 22 was used instead of Compound 4 to obtain Compound 25. ¹H NMR(dmso-d₆): δ 8.58 (d, J=0.8 Hz, 3H, (NO₂)₂C₆H₃O), 7.90 (s, 2H, CH═N),7.75 (dd, J=9.6, 3.2 Hz, 3H, (NO₂)₂C₆H₃O), 7.68 (s, 2H, m-H), 7.45 (s,2H, m-H), 6.30 (d, J=9.6, 3H, (NO₂)₂C₆H₃O), 3.63-3.57 (br, 2H,cyclohexyl-CH) 3.23-3.12 (m, 12H, NCH₂), 3.12-3.02 (m, 4H, NCH₂),2.08-1.96 (br, 4H, cyclohexyl-CH₂), 1.96-1.82 (br, 4H, cyclohexyl-CH₂),1.74 (s, 18H, CH₃), 1.70-1.52 (m, 12H, butyl-CH₂), 1.36-1.25 (m, 12H,butyl-CH₂), 0.92 (t, J=7.6 Hz, 18H, CH₃), 0.71 (t, J=8.0, 4H, SiCH₂),0.30 (s, 3H, SiCH₃), 0.29 (s, 3H, SiCH₃) ppm. ¹³C {¹H} NMR (dmso-d₆): δ168.42, 164.14, 161.48, 141.76, 136.85, 131.84, 131.67, 131.47, 131.12,129.94, 128.38, 127.88, 125.81, 125.05, 118.74, 70.12, 58.38, 55.68,34.22, 30.18, 28.78, 25.12, 24.32, 23.93, 23.48, 21.67, 20.08, 14.34ppm.

(14) Synthesis of Compound 26

The procedure for synthesizing Compound 25 was repeated except thatCompound 23 was used instead of Compound 22 to obtain Compound 26. ¹HNMR (dmso-d₆): δ 8.61 (br, 3H, (NO₂)₂C₆H₃O), 7.88 (br, 5H, (NO₂)₂C₆H₃Oand CH═N), 7.25 (s, 2H, m-H), 7.17 (s, 2H, m-H), 6.49 (d, J=9.6, 3H,(NO₂)₂C₆H₃O), 4.02 (br, 2H, iPr—), 3.59 (br, 2H, cyclohexyl-CH).3.36-3.10 (br, 16H, —NCH₂), 2.59 (br, 4H, —CH₂), 2.08-1.96 (br, 4H,cyclohexyl-CH₂), 1.92-1.78 (br, 4H, cyclohexyl-CH₂), 1.70-1.50 (m, 16H,—CH₂), 1.48-1.38 (br, 12H, iPr—CH₃), 1.34-1.22 (m, 16H, —CH₂), 0.92 (t,J=6.8 Hz, 18H, CH₃) ppm. ¹³C {¹H} NMR (dmso-d₆): δ 168.42, 164.14,161.48, 141.76, 136.85, 131.84, 131.67, 131.47, 131.12, 129.94, 128.38,127.88, 125.81, 125.05, 118.74, 70.12, 58.38, 55.68, 34.22, 30.18,28.78, 25.12, 24.32, 23.93, 23.48, 21.67, 20.08, 14.34 ppm.

(15) Synthesis of Compound 27

The procedure for synthesizing Compound 25 was repeated except thatCompound 24 was used instead of Compound 22 to obtain Compound 27. ¹HNMR (dmso-d₆): δ 8.75 (br, 3H, (NO₂)₂C₆H₃O), 7.94 (br, 3H, (NO₂)₂C₆H₃O),7.74 (s, 2H, CH═N), 7.28 (s, 2H, m-H), 7.21 (s, 2H, m-H), 6.45 (d,J=9.6, 3H, (NO₂)₂C₆H₃O), 3.58 (br, 2H, cyclohexyl-CH). 3.28-3.14 (br,16H, —NCH₂), 3.03-3.00 (m, 4H, —CH₂), 2.60 (br, 4H, —CH₂), 2.06-1.94(br, 4H, cyclohexyl-CH₂), 1.90-1.82 (br, 4H, cyclohexyl-CH₂), 1.71 (s,18H, —C(CH₃)₃), 1.66-1.50 (m, 28H, —CH₂), 1.36-1.26 (m, 16H, —CH₂), 0.91(t, J=6.8 Hz, 18H, CH₃) ppm.

EXAMPLE 5 Preparation of the Complex of Formula (6e)

(1) Synthesis of Compound 30

4-Bromo-2-tert-butylphenol (1.00 g, 4.37 mmol) was dissolved in THF (50mL) under a nitrogen atmosphere, tert-BuLi (1.7 M in pentane 5.86 g,15.28 mmol) was added thereto at −78° C. using a syringe. The reactionwas allowed to proceed while stirring at −78° C. for 2 hours.1,7-Dichloro-heptane-4-one (0.96 g, 5.24 mmol) and LiCl (0.22 g, 5.24mmol) were added to the reaction mixture while stirring −78° C. over 2hours. After the solution was stirred for 2 hours at −78° C., aqueoussaturated NH₄Cl solution (15 mL) was added to quench the reaction. Theproduct was extracted using diethyl ether (3×15 mL). After the combinedorganic phase was dried over anhydrous MgSO₄, the solvent was removedwith rotary evaporator to give an oily residue. The major side productof the reaction was 2-tert-butyl phenol, generated by the protonation ofthe lithiated compound. It was not easy to remove the side product fromthe hydrogenated product by column chromatography. Therefore, the sideproduct was eliminated by the following procedure: the oily residue wastransferred into a reparatory funnel, and then diethyl ether (10 mL) andaqueous KOH solution (22 w %, 5 mL) were added. The mixture wasvigorously shaken to give three phases. The upper layer was diethylether phase. The middle layer was a potassium phenolate of the desiredproducts. The bottom layer was an aqueous phase containing potassium2-tent-butylphenolate. After the bottom layer was discarded, aqueoussaturated NH₄Cl solution (5 mL) was added. By the addition, thephenolate anion of the desired products was protonated to be soluble inthe diethyl ether phase. The ether phase was collected and dried overanhydrous MgSO₄. The solvent was removed with a rotary evaporator togive an oily residue which was purified by column chromatography. Thebenzylic tertiary alcohol was obtained by eluting hexane and ethylacetate (v/v, 2:1). The obtained compound was then dissolved in ethanol(5 mL). Pd on activated charcoal (10 w %) was added, and then thesolution was stirred overnight at room temperature under an atmosphericpressure of H₂ gas. The solution was filtered over Celite, and thensolvent was removed with a rotary evaporator to give a residue, whichwas purified by column chromatography on silica gel eluting with hexaneand ethyl acetate (v/v, 2:1) to obtain Compound 30 (yield: 83%). ¹H NMR(CDCl₃): δ 7.02 (d, J=2.0 Hz, 1H, m-H), 6.84 (dd, J=8.0, 2.0 Hz, 1H,m-H), 6.62 (d, J=8.0 Hz, 1H, o-H), 4.93 (s, 1H, OH), 3.49 (t, J=5.6 Hz,4H, —CH₂Cl), 2.49 (quintet, J=4.8 Hz, 1H, —CH—), 1.88-1.75 (m, 4H, CH₂),1.72-1.61 (m, 4H, CH₂), 1.45 (s, 9H, —C(CH₃)₃) ppm. ¹³C {¹H} NMR(CDCl₃): δ 152.36, 135.86, 135.82, 126.02, 125.21, 115.38, 45.26, 44.34,34.56, 34.14, 30.66, 29.71 ppm

(2) Synthesis of Compound 31

The procedure for synthesizing Compound 30 was repeated except that4-bromo-2-isobutylphenol was used instead of 4-bromo-2-tert-butylphenolto obtain Compound 31. ¹H NMR (CDCl₃): δ 6.94 (d, J=2.0 Hz, 1H, m-H),6.83 (dd, J=8.0, 2.0 Hz, 1H, m-H), 6.69 (d, J=8.0 Hz, 1H, o-H), 4.73 (s,1H, OH), 3.48 (t, J=5.6 Hz, 4H, —CH₂Cl), 3.21 (septet, J=6.8 Hz, 1H,iPr—CH), 2.48 (quintet, J=4.8 Hz, 1H, —CH—), 1.82-1.60 (m, 8H, —CH₂),1.28 (d, J=6.8 Hz, 6H, iPr—CH₃) ppm. ¹³C {¹H} NMR (CDCl₃): δ 150.86,136.39, 134.21, 125.30, 125.12, 115.16, 45.27, 44.34, 34.17, 30.66,27.17, 22.71 ppm.

(3) Synthesis of Compound 32

The procedure for synthesizing Compound 30 was repeated except that4-bromo-2-methylphenol was used instead of 4-bromo-2-tert-butylphenol toobtain Compound 32. During the work up procedure, benzylic tert-alcoholalong with its H₂O eliminated, corresponding alkene also observed. TheH₂O eliminated alkene product was obtained from the column by elutingwith hexane and ethyl acetate (v/v, 10:1), and the benzylic tert-alcoholwas obtained by eluting the column with hexane and ethyl acetate (v/v,2:1). Both the compounds were combined for the reduction procedure. ¹HNMR (CDCl₃): δ 6.88 (d, J=2.0 Hz, 1H, m-H), 6.82 (dd, J=8.0, 2.0 Hz, 1H,m-H), 6.72 (d, J=8.0 Hz, 1H, o-H), 4.70 (s, 1H, OH), 3.49 (t, J=5.6 Hz,4H, —CH₂Cl), 2.46 (quintet, J=4.8 Hz, 1H, —CH—), 2.28 (s, 3H, —CH₃),1.82-1.60 (m, 8H, —CH₂) ppm.

(4) Synthesis of Compound 33

The procedure for synthesizing Compound 2 was repeated except thatCompound 30 was used instead of Compound 1 to obtain Compound 33 (yield:84%). ¹H NMR (CDCl₃): δ11.67 (s, 1H, OH), 9.85 (s, 1H, CHO), 7.30 (d,J=2.4 Hz, 1H, m-H), 7.16 (d, J=2.4 Hz, 1H, m-H), 3.49 (t, J=5.6 Hz, 4H,—CH₂Cl), 2.56 (quintet, J=5.2 Hz, 1H, —CH—), 1.88-1.81 (m, 2H, —CH₂),1.76-1.59 (m, 6H, —CH₂—), 1.44 (s, 9H, —C(CH₃)₃) ppm. ¹³C {¹H} NMR(CDCl₃): δ 196.74, 159.50, 138.29, 134.59, 133.17, 129.91, 120.25,45.02, 44.19, 34.91, 33.85, 30.51, 29.28 ppm.

(5) Synthesis of Compound 34

The procedure for synthesizing Compound 33 was repeated except thatCompound 31 was used instead of Compound 30 to obtain Compound 34. ¹HNMR (CDCl₃): δ 11.27 (s, 1H, OH), 9.86 (s, 1H, CHO), 7.28 (d, J=2.4 Hz,1H, m-H), 7.12 (d, J=2.4 Hz, 1H, m-H), 3.47 (t, J=5.6 Hz, 4H, —CH₂Cl),3.33 (septet, J=6.8 Hz, 1H, iPr—CH), 2.58 (quintet, J=5.2 Hz, 1H, —CH—),1.86-1.78 (m, 2H, —CH₂), 1.76-1.56 (m, 6H, —CH₂—), 1.26 (d, J=6.8 Hz,6H, -iPr—CH₃) ppm.

(6) Synthesis of Compound 35

The procedure for synthesizing Compound 33 was repeated except thatCompound 32 was used instead of Compound 30 to obtain Compound 35. ¹HNMR (CDCl₃): δ 11.18 (s, 1H, OH), 9.82 (s, 1H, CHO), 7.22 (d, J=2.4 Hz,1H, m-H), 7.14 (d, J=2.4 Hz, 1H, m-H), 3.49 (t, J=5.6 Hz, 4H, —CH₂Cl),2.54 (quintet, J=5.2 Hz, 1H, —CH—), 2.30 (s, 3H, —CH₃), 1.88-1.81 (m,2H, —CH₂), 1.76-1.59 (m, 6H, —CH₂—) ppm.

(7) Synthesis of Compound 36

The procedure for synthesizing Compound 3 was repeated except thatCompound 33 was used instead of Compound 2 and the crude product waspurified by column chromatography (ethanol:methylene chloride=1:20) toobtain Compound 36 (yield: 35%). ¹H NMR (CDCl₃): δ 11.76 (s, 1H, OH),9.92 (s, 1H, CHO), 7.53 (s, 1H, m-H), 7.35 (s, 1H, m-H), 3.36-3.22 (m,16H, —NCH₂), 2.82 (br, 1H, —CH—), 1.78-1.70 (m, 4H, —CH₂), 1.66-1.46 (m,16H, —CH₂), 1.42 (s, 9H, —C(CH₃)₃), 1.38-1.32 (m, 12H, butyl-CH₂), 0.93(t, J=7.6 Hz, 18H, CH₃) ppm. ¹³C {¹H} NMR (CDCl₃): δ 197.76, 159.67,138.70, 133.50, 132.63, 131.10, 120.40, 58.55, 41.45, 34.99, 32.28,29.31, 23.72, 19.59, 19.00, 13.54 ppm.

(8) Synthesis of Compound 37

The procedure for synthesizing Compound 36 was repeated except thatCompound 34 was used instead of Compound 33 to obtain Compound 37. ¹HNMR (CDCl₃): δ 11.27 (s, 1H, OH), 9.86 (s, 1H, CHO), 7.28 (d, J=2.4 Hz,1H, m-H), 7.12 (d, J=2.4 Hz, 1H, m-H), 3.47 (t, J=5.6 Hz, 4H, —CH₂Cl),3.33 (septet, J=6.8 Hz, 1H, iPr—CH), 2.58 (quintet, J=5.2 Hz, 1H, —CH—),1.86-1.78 (m, 2H, —CH₂), 1.76-1.56 (m, 6H, —CH₂—), 1.26 (d, J=6.8 Hz,6H, -iPr—CH₃) ppm.

(9) Synthesis of Compound 38

The procedure for synthesizing Compound 36 was repeated except thatCompound 35 was used instead of Compound 33 to obtain Compound 38. ¹HNMR (CDCl₃): δ 11.19 (s, 1H, OH), 9.89 (s, 1H, CHO), 7.48 (s, 1H, m-H),7.29 (s, 1H, m-H), 3.32-3.26 (m, 4H, —NCH₂), 3.10-3.06 (m, 12H, —NCH₂),2.77 (septet, J=6.8 Hz, 1H, —CH—), 2.24 (s, 3H, —CH₃), 1.76-1.64 (m, 8H,—CH₂), 1.58-1.44 (m, 16H, —CH₂), 1.34-1.29 (m, 8H, —CH₂), 0.90 (t, J=7.6Hz, 18H, CH₃) ppm.

(10) Synthesis of Compound 39

The procedure for synthesizing Compound 4 was repeated except thatCompound 36 was used instead of Compound 3 and the crude product waspurified by column chromatography (ethanol:methylene chloride=1:20) toobtain Compound 39 (yield: 85%). ¹H NMR (CDCl₃): δ 8.37 (s, 1H, CHO),7.00 (s, 2H, m-H), 3.44-3.38 (m, 1H, cyclohexyl-CH), 3.32-2.98 (m, 16H,—NCH₂), 2.63 (br, 1H, —CH—), 1.94-1.82 (m, 2H, cyclohexyl-CH₂),1.78-1.70 (m, 2H, cyclohexyl-CH₂), 1.68-1.58 (m, 4H, —CH₂—), 1.66-1.42(m, 16H, —CH₂), 1.38 (s, 9H. —C(CH₃)₃), 1.34-1.21 (m, 12H, butyl-CH₂),0.91 (t, J=7.2 Hz, 9H, butyl-CH₃), 0.80 (t, J=7.2 Hz, 9H, butyl-CH₃)ppm. ¹³C {¹H} NMR (CDCl₃): δ 164.79, 159.11, 137.71, 131.14, 128.78,127.38, 118.48, 71.96, 58.14, 57.93, 41.25, 34.89, 33.48, 33.20, 32.54,29.39, 24.22, 23.59, 23.48, 19.53, 19.38, 18.94, 13.51, 13.33 ppm.

(11) Synthesis of Compound 40

The procedure for synthesizing Compound 39 was repeated except thatCompound 37 was used instead of Compound 36 to obtain Compound 40. ¹HNMR (CDCl₃): δ 8.41 (s, 1H, CHO), 7.04 (s, 2H, m-H), 3.49-3.40 (m, 1H,cyclohexyl-CH), 3.31 (septet, J=6.8 Hz, 1H, iPr—CH), 3.18-2.98 (m, 16H,—NCH₂), 2.68 (br, 1H, —CH—), 1.92-1.82 (m, 2H, cyclohexyl-CH₂),1.78-1.70 (m, 2H, cyclohexyl-CH₂), 1.68-1.58 (m, 16H, —CH₂—), 1.66-1.42(m, 16H, —CH₂), 1.40-1.32 (m, 6H, butyl-CH₂), 1.30-1.18 (m, 12H. —CH₂and iPr—CH₃), 0.94 (t, J=7.2 Hz, 9H, butyl-CH₃), 0.84 (t, J=7.2 Hz, 9H,butyl-CH₃) ppm.

(12) Synthesis of Compound 41

The procedure for synthesizing Compound 39 was repeated except thatCompound 38 was used instead of Compound 36 to obtain Compound 41. ¹HNMR (CDCl₃): δ 8.37 (s, 1H, CHO), 7.02 (s, 2H, m-H), 3.43-3.41 (m, 1H,cyclohexyl-CH), 3.36-3.28 (m, 4H, —NCH₂), 3.18-3.05 (m, 12H, —NCH₂),2.68 (br, 1H, —CH—), 2.23 (s, 3H, —CH₃), 1.94-1.82 (m, 4H,cyclohexyl-CH₂), 1.78-1.60 (m, 8H, —CH₂), 1.58-1.40 (m, 16H, —CH₂),1.38-1.25 (m, 8H, —CH₂), 0.92 (t, J=7.2 Hz, 9H, butyl-CH₃), 0.86 (t,J=7.2 Hz, 9H, butyl-CH₃) ppm.

(13) Synthesis of Compound 42

The procedure for synthesizing Compound 5 was repeated except thatCompound 39 was used instead of Compound 4 to obtain Compound 42. ¹H NMR(dmso-d₆): δ 8.67 (br, 5H, (NO₂)₂C₆H₃O), 7.82 (br, 5H, (NO₂)₂C₆H₃O),7.72 (s, 2H, CH═N), 7.34 (s, 2H, m-H), 7.19 (s, 2H, m-H), 6.36 (br, 5H,(NO₂)₂C₆H₃O), 3.57-3.50 (br, 2H, cyclohexyl-CH), 3.28-2.84 (m, 32H,—NCH₂), 2.60-2.52 (br, 2H, —CH), 1.06-1.96 (br, 4H, cyclohexyl-CH₂),1.90-1.78 (br, 4H, cyclohexyl-CH₂), 1.70 (s, 18H, —C(CH₃)₃), 1.62-1.38(br, 48H, butyl-CH₂), 1.32-1.50 (m, 16H, —CH₂), 0.85 (t, J=7.2 Hz, 36H,CH₃ ppm. ¹³C {¹H} NMR (dmso-d₆): δ 164.01, 162.91, 143.19, 132.15,130.85, 129.51, 128.59, 128.01 (br), 125.79 (br), 119.56, 69.71, 58.37,58.14, 56.37, 42.94, 36.28, 33.56, 31.03, 30.13, 24.95, 23.66, 19.85,14.12 ppm.

(14) Synthesis of Compound 43

The procedure for synthesizing Compound 42 was repeated except thatCompound 40 was used instead of Compound 39 to obtain Compound 43. ¹HNMR (dmso-d₆): δ 8.61 (br, 5H, (NO₂)₂C₆H₃O), 7.86 (s, 2H, CH═N), 7.81(br, 5H, (NO₂)₂C₆H₃O), 7.31 (s, 2H, m-H), 7.17 (s, 2H, m-H), 6.36 (br,5H, (NO₂)₂C₆H₃O), 4.02-3.62 (br, 2H, iPr—CH₃), 3.57-3.48 (br, 2H,cyclohexyl-CH), 3.29-2.90 (m, 32H, —NCH₂), 2.08-1.98 (br, 4H,cyclohexyl-CH₂), 1.87-1.74 (br, 4H, cyclohexyl-CH₂), 1.66-1.34 (br, 52H,—CH₂), 1.29-1.12 (m, 36H, —CH₂), 0.89 (br, 36H, butyl-CH₃) ppm.

(15) Synthesis of Compound 44

The procedure for synthesizing Compound 42 was repeated except thatCompound 41 was used instead of Compound 39. ¹H NMR (dmso-d₆): δ 8.62(br, 5H, (NO₂)₂C₆H₃O), 7.70 (br, 7H, (NO₂)₂C₆H₃O and CH═N), 7.33 (s, 2H,m-H), 7.21 (s, 2H, m-H), 6.33 (br, 5H, (NO₂)₂C₆H₃O), 3.56-3.50 (br, 2H,cyclohexyl-CH), 3.30-2.87 (m, 32H, —NCH₂), 2.61 (s, 6H, —CH₃), 2.08-1.96(br, 4H, cyclohexyl-CH₂), 1.88-1.76 (br, 4H, cyclohexyl-CH₂), 1.66-1.32(br, 52H, —CH₂), 1.29-1.10 (m, 36H, —CH₂), 0.84 (br, 36H, butyl-CH₃)ppm.

EXAMPLE 6 Preparation of the Complex of Formula (6f)

Synthesis of Compound 45

Compound 4 (0.050 g, 0.043 mmol) and CrCl₂ (0.005 g, 0.043 mmol) weredissolved in tetrahydrofuran (2 mL) under a nitrogen atmosphere, and thereaction was allowed to proceed overnight while stirring at roomtemperature. The resulting solution was exposed to air, trichloroaceticacid was added thereto, and stirred for a day. Sodium trichloroacetatewas added to the reaction mixture, and stirred for 3 hours. Theresulting solution was filtered through cellite, and the solvent wasremoved from the filtrate. The residue was dissolved in methylenechloride, and the resulting solution was filtered. The solvent wasremoved from the filtrate to obtain Compound 45 as a bright brown solid.

EXAMPLES 7 TO 22 Copolymerization of Polycarbonates

Using the catalyst specified in Table 1, each of the compound preparedin Examples and propylene oxide (10.0 g, 172 mmol) were placed in a 50mL bomb reactor and the reactor was sealed. The reactor was immersed inan oil bath having a set temperature and the reactants in the reactorwere stirred under a carbon dioxide partial pressure of 20 bar. With theprogress of the reaction, the carbon dioxide pressure dropped, and whenthe carbon dioxide pressure dropped by about 3 bar, the reaction wasterminated by venting carbon dioxide. The resulting viscous liquid wasadded dropwise to methanol and stirred for 12 hours to induce theformation of a polymer as a white solid. The resultant polymer wasisolated and dried in a vacuum at 60° C. The results are shown in Table1.

COMPARATIVE EXAMPLES 1 TO 5

To compare the reactivities of the inventive catalysts with that of theknown catalysts, copolymerization was performed as described in Example7 except that Compounds 46 and 47 were used as comparative catalysts.

TABLE 1

Copolymerization results^([a]) Select- Ex. Comp. [PO]/ Temp ivity^([c])M_(w)/ No. no. [Catalyst] (° C.) TOF^([b]) TON^([b]) (%) M_(n) ^([d])M_(n) ^([d])  7 5 25000 50 650 4600 100 75000 1.23  8 5 25000 70 24002400 94 61000 1.19  9 5 25000 80 3300 3300 94 71000 1.25 10 5 25000 903500 3500 90 80000 1.32 11 5 50000 80 3200 14500 84 53000 1.35 12 725000 80 1500 3000 89 44000 1.58 13 25 25000 80 3100 3100 95 11000 1.4914 26 25000 80 3000 3000 89 36000 1.52 15 27 25000 80 270 1600 70 420001.20 16 42 25000 80 1300 2500 84 38000 1.34 17 43 25000 80 7900 5300 >9976000 1.32 18 44 25000 80 26000 6400 >99 114000 1.29 19 44 50000 8026000 13000 >99 208000 1.20 20 44 100000 80 22000 22000 >99 285000 1.1821 44 150000 80 12400 31000 96 175000 1.20 22 45 10000 80 1300 2700 80Com. 46 25000 80 0 0 0 Ex. 1^([e]) Com. 46 2000 45 1400 980 97 260001.01 Ex. 2^([f]) Com. 47 25000 60 360  1800^([g]) 76 n.d. n.d.^([g]) Ex.3 Com. 47 25000 80 370  1100^([g]) 60 n.d. n.d.^([g]) Ex. 4 Com. 47 200060 610 610 90 7000 1.22 Ex. 5 [PO]/[Catalyst]: molar ratio of propyleneoxide to catalyst. ^([a])Polymerization conditions: propylene oxide(10.0 g, 172 mmol), CO₂ (initial pressure, 2.0 MPa). TON^([b]) turnovernumber, i.e., the number of molecules that one mole of catalyst canconvert before becoming inactivated TOF^([b]) turnover frequency, i.e.,turnover number per unit time. These values are based on the weight ofthe resulting polymer which does not include the amount of the sideproduct, cyclic carbonate. TON and TOF are calculated as below: TON =the weight of the resulting polymer (g)/[102*the mol of consumedcatalyst]; TOF = TON/[hours (h)]. ^([c])Selectivity was calculated by ¹HNMR spectroscopy analysis of the resulting polymer solution. ^([d])Themolecular weight and the molecular weight distribution measured by GPC,calibrating with polystyrene having a single distribution of molecularweight as the standard material. ^([e])Only cyclic carbonate wasobtained at TOF of 1950 h⁻¹. ^([f])Polymerization data reported in theliterature [X.-B. Lu, L. Shi, Y.-M. Wang, R. Zhang, Y.-J. Zhang, X.-J.Peng, Z.-C. Zhang, B.Li, J. Am. Chem. Soc. 2006, 128, 1664]. ^([g])Sinceonly a low molecular weight oligomer was obtained, the molecular weightof polymer was not measured, and, thus, TON and TOF were calculated by¹H NMR spectroscopy analysis of the resulting solution.^([h])Polymerization data reported in the literature [K. Nakano, T.Kamada, K. Nozaki, Angew. Chem. 2006, 118, 7432; Angew. Chem. Int. Ed.2006, 45, 7274.].

As shown in Table 1, Compound 44 showed a high copolymerization activityat a high ratio of 100,000 of the [propylene oxide]/[catalyst] ratio andeven at a high temperature of 80° C. (see example 20). Compound 44 wascapable of producing the copolymer with such a high TON and TOF valuesas 22,000 and 22,000 h⁻¹ even under the condition of [propyleneoxide]/[catalyst] ratio of 100,000.

The comparative catalyst Compound 46 exhibited a TOF value of 1,400 h⁻¹under the conditions of [propylene oxide]/[catalyst] ratio of 2,000 andthe temperature of 45° C. (see Comparative Example 2), but do notprovide any copolymer at the temperature of 80° C. and at [propyleneoxide]/[catalyst] ratio of 25,000 (see Comparative Example 1).

A catalyst system of Compound 47 having tertiary ammonium salt hasrecently been reported [K. Nakano, T. Kamada, K. Nozaki, Angew. Chem.2006, 118, 7432; Angew. Chem. Int. Ed. 2006, 45, 7274.]. AlthoughCompound 47 showed a high selectivity of 90% at 60° C., the selectivitydecreased with the increase of the reaction temperature or the[propylene oxide]/[catalyst] ratio (see Comparative Examples 3 to 5).Furthermore, the TOF value of Compound 47 at a high [propyleneoxide]/[catalyst] ratio (about 300 h⁻¹) was remarkably smaller than thatof the inventive compound 44 (about 22,000 h⁻¹).

Compound 44 showed a high selectivity of >99% at a high temperature anda high [propylene oxide]/[catalyst] ratio, in addition to high TOF andTON values.

Using the inventive catalyst, a high molecular weight polymer wasobtained. As high molecular weight as M_(n) is 285,000 is achieved usingthe inventive catalyst. The molecular weights of the polymers producedby using Compound 46 were less than 30,000. In addition, when Compound47 was used as a catalyst, only a low molecular weight oligomer wasobtained.

EXAMPLES 23 TO 33 Recovering of Catalyst Example 23

Step 1

7.0 mg of Compound 44 prepared in Example 5 and propylene oxide (9.0 g,150 mmol) were placed in a 50 mL bomb reactor and the reactor wassealed. The reactor was immersed in an oil bath having a set temperatureof 80° C., the reactants in the reactor were stirred for 15 minutes. Thereaction was allowed to proceed for 30 minutes under a carbon dioxidepartial pressure of 20 bar. The reaction was terminated by ventingcarbon dioxide.

For the comparison, 20 g of propylene oxide was added to the resultingviscous liquid, and the content of cobalt in the copolymer solution wasdetermined with an ICP-mass spectroscopy (Table 2: Comparative example6). Further, after the solvent was removed from the solution, theresidue (copolymer) was dissolved in 20 ml of methylene chloride, anddetermined optical density thereof with UV-Visible Spectrometer (FIG.4). Propylene oxide was removed from the solution under a vacuum toobtain 4.1 g of the copolymer solution containing the polycarbonate andthe complex was obtained (TON=13,000 and TOF=26,000).

Step 2

21 mg of a high molecular weight polyacrylate (PPA: Mv=3,000,000, 0.5%cross-linked, Aldrich) was added to the copolymer solution, and stirredat the room temperature for 2 hours. The resulting solution was filteredthrough cellite. The content of cobalt in the filtered solution wasdetermined by using an ICP-mass spectroscopy (Table 2). After thesolvent was removed from the copolymer solution, the copolymer wasdissolved in 20 ml of methylene chloride, and its optical density wasdetermined with UV-Visible Spectrometer (FIG. 4).

Example 24

The procedure of Example 23 was repeated except that a low molecularweight polyacrylate (Mv=450,000, 0.5% cross-linked) was used instead ofthe high molecular weight polyacylate. The content of cobalt in thefiltered solution was determined by using an ICP-mass spectroscopy(Table 2). After the solvent was removed from the copolymer solution,the copolymer was dissolved in 20 ml of methylene chloride, and itsoptical density was determined with UV-Visible Spectrometer (FIG. 4).

Example 25

The resulting solution of the step 1 of Example 23 was filtered througha glass filter filled with silica gel (400 mg, particle size 0.040-0.063mm, 230-400 mesh, Merck). The content of cobalt in the filtered solutionwas determined by using an ICP-mass spectroscopy (Table 2). After thesolvent was removed from the copolymer solution, the copolymer wasdissolved in 20 ml of methylene chloride, and its optical density wasdetermined with UV-Visible Spectrometer (FIG. 4).

Example 26

The procedure of Example 25 was repeated except that the glass filterwas filled with alumina (1.0 g, neutral, about 150 mesh, Sigma-Aldrich).The content of cobalt in the filtered solution was determined by usingan ICP-mass spectroscopy (Table 2). After the solvent was removed fromthe copolymer solution, the copolymer was dissolved in 20 ml ofmethylene chloride, and its optical density was determined withUV-Visible Spectrometer (FIG. 4).

TABLE 2 Example No. Cobalt content (ppm) Comparative Example 6 38Example 23 9.2 Example 24 13 Example 25 1.2 Example 26 3.6

Example 27

The solid compound collected from the filtration of Example 23 wasdispersed in methylene chloride solvent, 14 mg of 2,4-dinitrophenol wasadded thereto, and the solution turned red. The red solution wasfiltered and the solvent was removed under a vacuum. The residue wastreated with diethyl ether to recover 5 mg of the inventive catalyticcomplex as a solid. The recovered catalysts showed same ¹H-NMR spectrumand the same activity that observed for fresh virgin catalyst.

Example 28

The procedure of Example 27 was repeated with the solid compoundcollected from Example 24, and 6 mg of the inventive catalytic complexwas recovered. The recovered catalysts showed same ¹H-NMR spectrum andthe same activity that observed for fresh virgin catalyst.

Examples 29 and 30

The procedure of Example 27 was repeated except that the solid compoundscollected from Examples 25 and 26 were dispersed in methanol solvent,respectively. According to ¹H-NMR analyses, the recovered catalystscomprise additional 2 moles of 2,4-dinitrophenolate per mole of cobalt,which showed about ⅔ of the initial activity.

Examples 31 and 32

Solid compounds collected from the filtration of Examples 25 and 26 wererespectively dispersed into methanol saturated with NaBF₄, and thesolution turned red. The red solution was filtered, and the filtrate waswashed with methanol saturated with NaBF₄ until the solution becamecolorless. The solvent was removed under a vacuum, and the residue wasdissolved in methylene chloride. An excessive amount of solid sodium2,4-dinitrophenolate (4 equivalents based on added catalyst) and2,4-dinitrophenol (2 equivalent) were added to the methylene chloridesolution and stirred overnight. The solution was filtered over Celite,and the solvent was removed from the filtered solution to obtain thecatalyst as a brown powder. The recovered catalysts showed same ¹H-NMRspectrum and the same activity that observed for fresh virgin catalyst.

Example 33

The procedure of Example 23 was repeated except that 95 mg of theCompound 44 prepared in Example 5 and propylene oxide (250.0 g) wereplace in a 500 mL bomb reactor. The reaction was allowed to proceed for1 hour and 5 minutes.

250 g of propylene oxide was added to the resulting viscous liquid. Theresulting solution was filtered through a silica gel column (12 g,230-400 mesh, Merck). The solvent was recycled by a vacuum transfer and92 g of copolymer was obtained (TON is 21,000 and TOF is 19,000 h⁻¹)

The red solid collected on the surface layer of the silica was dissolvedin methanol saturated with NaBF₄, the resulting solution was filteredand washed with methanol saturated with NaBF₄ until the solution becamecolorless. The solvent was removed under a vacuum, and the residue wasdissolved into methylene chloride. An excessive amount of solid sodium2,4-dinitrophenolate (4 equivalents based on added catalyst) and2,4-dinitrophenol (2 equivalent) were added to the resulting solutionand stirred overnight. The solvent was removed to obtain the catalyst asa brown powder (82 mg, recovery yield=86%). The recovered catalystsshowed same ¹H-NMR spectrum and it could be used for subsequent batchwithout significant loss of activity. Table 2 shows the polymerizationresults using the recovered catalyst. In the repeated polymerizations,some reductions of the selectivity from >99% to 97-98% and the molecularweights from about 300,000 to about 200,000 was observed. The recoveryyields were 85-89%; some of this loss is attributed to the necessarilyincomplete transfer of the polymerization solution from the reactor tothe filtration apparatus. The lost catalyst was supplemented with afresh material for each subsequent batch.

TABLE 3 90-g scale CO₂/(propylene oxide) copolymerization using therecovered catalyst of Compound 44. Run Time Yield # (h) (g) TONSelectivity Mn × 10⁻³ Mw/Mn 1st 65 92 21000 >99 296 1.19 2nd 85 90 2100098 172 1.41 3rd 85 89 21000 97 176 1.34 4th 80 88 21000 98 190 1.22 5th90 85 20000 97 210 1.21

While the invention has been described with respect to the specificembodiments, it should be recognized that various modifications andchanges may be made by those skilled in the art to the invention whichalso fall within the scope of the invention as defined by the appendedclaims.

1. A process for producing a polycarbonate comprising subjecting anepoxide and carbon dioxide to a copolymerization reaction in thepresence of a complex, wherein the complex is represented by formula(4a)

wherein: M is Co or Cr; X′ is each independently halogen; C₆-C₂₀ aryloxyunsubstituted or substituted by nitro; or C₁-C₂₀ carboxy unsubstitutedor substituted by halogen; A is oxygen; Q is trans-1,2-cyclohexylene,ethylene or substituted ethylene; R¹, R², R⁴, R⁶, R⁷ and R⁹ arehydrogen; R⁵ and R¹⁰ are each independently hydrogen, tert-butyl, methylor isopropyl; one or both of R³ and R⁸ are —[YR⁴¹_(3-m){(CR⁴²R⁴³)_(n)NR⁴⁴R⁴⁵R⁴⁶}_(m)]X′_(m) or —[PR⁵¹R⁵²═N═PR⁵³R⁵⁴R⁵⁵]X′,the other being hydrogen, methyl, isopropyl or tert-butyl; Y is C or Si;R⁴¹, R⁴², R⁴³, R⁴⁴, R⁴⁵, R⁴⁶, R⁵¹, R⁵², R⁵³, R⁵⁴ and R⁵⁵ are eachindependently hydrogen; C₁-C₂₀ alkyl; C₁-C₂₀ alkyl having one or morefunctional moieties selected from the group consisting of halogen,nitrogen, oxygen, silicon, sulfur and phosphorous; C₂-C₂₀ alkenyl;C₂-C₂₀ alkenyl having one or more functional moieties selected from thegroup consisting of halogen, nitrogen, oxygen, silicon, sulfur andphosphorous; C₇-C₂₀ alkylaryl; C₇-C₂₀ alkylaryl having one or morefunctional moieties selected from the group consisting of halogen,nitrogen, oxygen, silicon, sulfur and phosphorous; C₇-C₂₀ arylalkyl;C₇-C₂₀ arylalkyl having one or more functional moieties selected fromthe group consisting of halogen, nitrogen, oxygen, silicon, sulfur andphosphorous; or a metalloid radical of group XIV metal substituted byhydrocarbyl, two of R⁴⁴, R⁴⁵ and R⁴⁶, or two of R⁵¹, R⁵², R⁵³, R⁵⁴ andR⁵⁵ being optionally fused together to form a bridged structure; m is aninteger in the range of 1 to 3; and n is an integer in the range of 1 to20.
 2. The process of claim 1, wherein the epoxides are selected fromthe group consisting of C₂-C₂₀ alkylene oxide unsubstituted orsubstituted by halogen or alkoxy, C₄-C₂₀ cycloalkene oxide unsubstitutedor substituted by halogen or alkoxy, and C₈-C₂₀ styrene oxideunsubstituted or substituted by halogen, alkoxy or alkyl.
 3. The processof claim 1, wherein the complex is represented by any one of formulae(5a) to (5e):

wherein M is Co or Cr; R⁶¹, R⁶² and R⁶³ are each independently hydrogen,methyl, isopropyl or tert-butyl; X is halogen; C₆-C₂₀ aryloxy; C₆-C₂₀aryloxy having one or more functional moieties selected from the groupconsisting of halogen, nitrogen, oxygen, silicon, sulfur andphosphorous; C₁-C₂₀ carboxy; C₁-C₂₀ carboxy having one or morefunctional moieties selected from the group consisting of halogen,nitrogen, oxygen, silicon, sulfur and phosphorous; C₁-C₂₀ alkoxy; C₁-C₂₀alkoxy having one or more functional moieties selected from the groupconsisting of halogen, nitrogen, oxygen, silicon, sulfur andphosphorous; C₁-C₂₀ alkylsulfonato; C₁-C₂₀ alkylsulfonato having one ormore functional moieties selected from the group consisting of halogen,nitrogen, oxygen, silicon, sulfur and phosphorous; C₁-C₂₀ amido ; orC₁-C₂₀ amido having one or more functional moieties selected from thegroup consisting of halogen, nitrogen, oxygen, silicon, sulfur andphosphorous; and n is an integer in the range of 1 to
 20. 4. The processof claim 3, wherein the complex is a compound of any one of formulae(6a) to (6f):

wherein X is 2,4-dinitrophenoxy;

wherein X is 2,4-dinitrophenoxy;

wherein X is Cl;

wherein X is 2,4-dinitrophenoxy, and R is methyl, isopropyl ortent-butyl;

wherein X is 2,4-dinitrophenoxy, and R is methyl, isopropyl ortert-butyl;

wherein X is Cl.
 5. A process for producing a polycarbonate comprisingthe steps of: subjecting an epoxide and carbon dioxide to acopolymerization reaction in the presence of a complex; treating thereaction mixture containing the polycarbonate and the complex with acomposite-forming material to form a composite of the complex and thecomposite-forming material; wherein the composite-forming material is aninorganic solid, a polymer, or a mixture thereof; removing the compositefrom the reaction mixture; and recovering the complex from the compositeby treating the composite in a medium which does not dissolve thecomposite-forming material with an acid and/or a non-reactive metalsalt, and isolating the complex released into the medium: wherein theepoxide is selected from the group consisting of C₂-C₂₀ alkylene oxideunsubstituted or substituted by halogen or alkoxy, C₄-C₂₀ cycloalkeneoxide unsubstituted or substituted by halogen or alkoxy, and C₈-C₂₀styrene oxide unsubstituted or substituted by halogen, alkoxy or alkyl;and the complex is represented by formula (4a); the inorganic solid issilica, and the polymer has carboxylic acid group; and the non-reactivemetal salt is M′BF₄, wherein M′ is Li, Na or K:

M is Co or Cr; X′ is each independently halogen; C₆-C₂₀ aryloxyunsubstituted or substituted by nitro; or C₁-C₂₀ carboxy unsubstitutedor substituted by halogen; A is oxygen; Q is trans-1,2-cyclohexylene,ethylene or substituted ethylene; R¹, R², R⁴, R⁶, R⁷ and R⁹ arehydrogen; R⁵ and R¹⁰ are each independently hydrogen, tert-butyl, methylor isopropyl; one or both of R³ and R⁸ are —[YR⁴¹_(3-m){(CR⁴²R⁴³)_(n)NR⁴⁴R⁴⁵R⁴⁶}_(m)]X′_(m) or —[PR⁵¹R⁵²═N═PR⁵³R⁵⁴R⁵⁵]X′,the other being hydrogen, methyl, isopropyl or tert-butyl; Y is C or Si;R⁴¹, R⁴², R⁴³, R⁴⁴, R⁴⁵, R⁴⁶, R⁵¹, R⁵², R⁵³, R⁵⁴ and R⁵⁵ are eachindependently hydrogen; C₁-C₂₀ alkyl; C₁-C₂₀ alkyl having one or morefunctional moieties selected from the group consisting of halogen,nitrogen, oxygen, silicon, sulfur and phosphorous; C₂-C₂₀ alkenyl;C₂-C₂₀ alkenyl having one or more functional moieties selected from thegroup consisting of halogen, nitrogen, oxygen, silicon, sulfur andphosphorous; C₇-C₂₀ alkylaryl; C₇-C₂₀ alkylaryl having one or morefunctional moieties selected from the group consisting of halogen,nitrogen, oxygen, silicon, sulfur and phosphorous; C₇-C₂₀ arylalkyl;C₇-C₂₀ arylalkyl having one or more functional moieties selected fromthe group consisting of halogen, nitrogen, oxygen, silicon, sulfur andphosphorous; or a metalloid radical of group XIV metal substituted byhydrocarbyl, two of R⁴⁴, R⁴⁵ and R⁴⁶, or two of R⁵¹, R⁵², R⁵³, R⁵⁴ andR⁵⁵ being optionally fused together to form a bridged structure; m is aninteger in the range of 1 to 3; and n is an integer in the range of 1 to20.
 6. The process of claim 5, wherein the step of treating the reactionmixture with the composite-forming material is conducted by adding thecomposite-forming material to the reaction mixture and the composite isseparated from the reaction mixture by filtration; or by passing thereaction mixture through a column filled with the composite-formingmaterial.
 7. The process of claim 5, wherein the complex is representedby formula (5e); the composite forming material is silica orcross-linked poly(acrylic acid); the acid is 2,4-dinitrophenol; and thenon-reactive metal salt is NaBF₄;

wherein M is Co; R⁶¹ and R⁶² are methyl; X is 2,4-dinitrophenoxy; and nis 3.